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Showing posts with label Aspirin. Show all posts
Showing posts with label Aspirin. Show all posts

Wednesday 1 November 2017

OAT3 inhibitors for Bumetanide - Probenecid, but also Aspirin, Chlorogenic acid (Coffee), Epicatechin (Cocoa, Cinnamon) and more.


Today’s post is about OAT3, highlighted by the green lines.
The interventions reduce renal excretion and raise plasma
concentration rather than directly improving transport across the BBB

Today’s post is a collaboration. Our reader Ling pointed out research trying to boost the bioavailability of bumetanide using something clever called an OAT3 inhibitor.  This would reduce the rate at which the body excretes bumetanide and thus potentially improve its therapeutic effect.
Petra, our reader from Greece, pointed out that in her son Bumetanide seemed to work better when taken with Greek coffee and that that Greek Grandpas like to take their diuretics with a steaming Greek coffee.
Most people, me included, automatically think caffeine when someone mentions coffee.
So I assumed that caffeine might be an OAT3 inhibitor and I did make some experiments on that basis. There is no research data to support caffeine as an OAT3 inhibitor.
Recently I was again looking for other potential Bumetanide boosters.  The obvious one is called Probenecid.  Probenecid is used to treat gout because it lowers uric acid.
Aspirin has some odd effects; low dose aspirin will raise uric acid, but high dose aspirin will lower it. Aspirin is an OAT3 inhibitor.
OATs are a very niche subject, to add to the confusion sometimes you are better looking for SLC22A8, the gene that encodes the transporter. 
There was an earlier post on this subject, which showed that many NSAIDs inhibit OAT3, including Knut’s favourite Ponstan. They are not so well suited to continued use.

At the end of my little investigation I figured it out; there are many OAT3 inhibitors available, including some in your kitchen.  


Key points on OAT3 (Organic Anion Transporter 3)
If you want to increase the peak concentration and indeed the half-life of a drug that is excreted from the body by OAT3 (organic anion transporter 3), an OAT inhibitor is what you need.
The drug Probenecid is by far the best known OAT3 inhibitor and it is very potent. It has long been to boost the performance of penicillin type antibiotics to treat tough bacterial infections.
Probenecid, if available, may very well be the ideal bumetanide booster.
For adults a simple option is Greek/Turkish coffee. I see little downside as long as you can handle the caffeine. The Greeks live a long time and drink plenty of coffee.
For those who do not like caffeine you can go to active components within the coffee, which seem to be the chlorogenic acids (1,3- and 1,5-dicaffeoylquinic acid). They are sold as a weight loss supplement, the long established version is the French-made Svetol, but there are now others. They still contain 2- 3% caffeine.
Epicatechin, found in cinnamon, dark chocolate and high flavanol cocoa is another OAT3 inhibitor. Cocoavia, made by Mars, is used by some readers of this blog. Cocoa flavanols do clever things with nitric oxide (NO) and have been shown to improve mild cognitive impairment (MCI) and heart health by improving blood vessel elasticity.
Catechins are flavanols belonging to a family of closely related compounds, such as epicatechin, epigallocatechin, epicatechin gallate (EGC), and epigallocatechin gallate (EGCG). They are all slightly different. Catechin itself is not an OAT3 inhibitor; EGCG may or may not be.
Low dose aspirin is likely the cheapest OAT3 inhibitor. It also increases peripheral circulation, which could benefit some. Low dose aspirin has the downside of a small bleeding risk, mainly in old people, and there is a risk of Reye’s syndrome if given during/after a viral infection.
I think for adults a Greek coffee may be the best. For people who have a profound benefit from Bumetanide, I think they should look into Probenecid.
Personally I think Svetol is worth a try.
Coffee that has been extensively processed (just as we saw with cocoa) may not have the same chlorogenic acid content as the more gritty coffee used in the Balkans. Coffee consumption is actually associated with many neurological benefits, reducing the incidence of Parkinson’s and Alzheimer’s; the common mistake in research is the assumption that the effect must be from caffeine.











  
The health effects of decaffeinated Coffee
My eureka moment in this post was reading about gout and coffee and then decaffeinated coffee. 




So then it was a question of finding what in coffee could be the OAT3 inhibitor. At which point I found a very insightful paper that tells you everything, once you realise that:

Coffee = chlorogenic acids  = 1,3- and 1,5-dicaffeoylquinic acid


Five compounds, 1,3- and 1,5-dicaffeoylquinic acid, ginkgolic acids (15 : 1) and (17 : 1), and epicatechin, significantly inhibited hOAT3 transport under similar conditions

3.2. Inhibition of hOAT3 by Natural Anionic Compounds and Flavonoids

Human OAT3 expressing cells showed about 4-fold greater accumulation of ES as compared to background control cells ( versus  pmol mg 10  , resp.). Similar to hOAT1, hOAT3-mediated ES uptake was completely (>96% inhibition) blocked by probenecid (Figure 4). Five of the compounds, 1,3- and 1,5-dicaffeoylquinic acid, epicatechin, and ginkgolic acids (15 : 1) and (17 : 1), significantly inhibited hOAT3-mediated transport at 50-fold excess (Figure 4). 1,3-Dicaffeoylquinic acid and ginkgolic acid (17 : 1) exhibited 41% inhibition, while 30–35% reduction of hOAT3-mediated ES uptake was observed for 1,5-dicaffeoylquinic acid, epicatechin, and ginkgolic acid (15 : 1). Catechin, 18β-glycyrrhetinic acid, and ursolic acid failed to produce significant inhibition. Based on the level of inhibition observed, values for all of these compounds would be greater than 50 μM, much higher than clinically relevant concentrations (Table 1). Therefore, further dose-response studies were not performed.










Lay off the Lycopene?
Lycopene does the opposite of what we want. Too much lycopene may lower the effectiveness of a drug that is excreted via OAT3. 

2.29. Lycopene

Lycopene is a carotenoid pigment found in tomato [94]. Lycopene from dietary sources has been shown to reduce the risk of some chronic diseases including cancer and cardiovascular disorders [95]. The administration of lycopene significantly normalized the kidney function and antioxidant status of CSP-treated animals. Furthermore, lycopene also increased the expression of the organic anion and cation transporters (OAT and OCT, resp.) including OAT1, OAT3, OCT1, and OCT2 in the renal tissues [9698]. In addition, lycopene also decreased the renal efflux transporters (multidrug resistance-associated protein [MRP]-2 and MRP4) levels and induced Nrf2 activation, which activated the antioxidant defense system [99]. Furthermore, lycopene protected against CSP-induced renal injury by modulating proapoptotic Bax and antiapoptotic Bcl-2 expressions and enhancing heat shock protein (HSP) expression [97].

https://www.hindawi.com/journals/omcl/2016/4320374/                                                                                                                  

Aspirin
I actually started out this post by looking at what dose of aspirin might be effective in inhibiting OAT3.  We do know that Aspirin is indeed an OAT3 inhibitor.  


I did find the answer, but along the way you do end up having to look at uric acid. 
Uric acid is taken up by OAT1 and OAT3 from the blood and reabsorbed into renal tubular cells via URAT1 Uric acid is taken up by OAT1 and OAT3 from the blood and reabsorbed into renal tubular cells via URAT1Uric acid is taken up by OAT1 and OAT3 from the blood and reabsorbed into renal tubular cells via URAT1. 
Uricosuric drugs increase the excretion of uric acid in the urine, thus reducing the concentration of uric acid in blood plasma. 
In general, uricosuric drugs act on as urate transporter 1 (URAT1). URAT1 is the central mediator in the transport of uric acid from the kidney into the blood.  By their mechanism of action, some uricosurics (such as  probenecid) increase the blood plasma concentration of certain other drugs and their metabolic products  – this is their effect on OAT3.
Probenecid is a medication that increases uric acid excretion in the urine.
Atorvastatin is a so-called secondary uricosuric. High dose aspirin should also be called a secondary uricosuric.
Antiuricosuric drugs raise serum uric acid levels and lower urine uric acid levels. These drugs include all diuretics and low dose aspirin. 
Low dose aspirin inhibits OAT1 and OAT3 which reduces urate secretion, but high dose aspirin inhibits URAT1 and reduces urate re absorption. This is sometimes known as the biphasic effect.
So low dose aspirin will increase plasma uric acid, but high dose aspirin has the same effect as Probenecid, it lowers plasma uric acid levels.
So Aspirin and Probenecid both affect URAT1 and OAT3. 






At what dose is Aspirin an OAT3 inhibitor?
If we just want aspirin to inhibit OAT3 and not inhibit URAT1, what dose is effective? Fortunately this has been answered in the research. The typical low dose of aspirin (75mg) used preventatively in older people is OAT3 inhibiting, it raises plasma uric acid.  





Salicylate

Salicylic acid and its derivatives are the most prescribed analgesic, antipyretic, and anti-inflammatory agents. Salicylates have a “paradoxical effect” on the handling of uric acid by the kidney. The action of salicylates on uric acid excretion depends on the dose of salicylates. At doses of less than 2.5 g/day, salicylates cause the retention of uric acid by blocking the tubular secretion of uric acid, while at dose of higher than 3 g/day, they cause increased urinary excretion of uric acid [70]. Mini-dose aspirin, even at a dosage of 75 mg/day, caused a decrease in uric acid excretion and raised serum uric acid level [71]. It has been suggested that the “paradoxical effect” of salicylate can be explained by two modes of salicylate interaction with URAT1: (1) acting as an exchange substrate to facilitate uric acid reabsorption, and (2) acting as an inhibitor for uric acid reabsorption [72]. Low dose of salicylate interact with OAT1/OAT3, the uric acid secreters [73].

Low dose aspirin leads to decreased renal excretion of uric acid and raised serum uric acid levels, which can cause a gout attack in those predisposed to this condition.
High doses of aspirin lower serum uric acid concentration.

Reye’s Syndrome
In children aspirin is very rarely used because of the risk of Reye’s syndrome. Reye’s syndrome causes severe liver and brain damage. It is a type of severe mitochondrial failure that can occur after a viral infection like flu or chickenpox, but it almost only occurs when aspirin has been prescribed. Nobody knows for sure the exact mechanism of the disease.
So do not give aspirin to children with a viral infection.  We already know to avoid paracetamol/acetaminophen (Tylenol in the US) in babies/children and people with autism. Paracetamol/acetaminophen depletes the body’s key antioxidant GSH. 
If someone overdoses on Paracetamol/acetaminophen you give them a high dose of NAC to prevent death. 


Conclusion
Given how long it takes to develop new drugs, I think that improving the pharmokinetics of bumetanide is a pretty obvious thing to do. 
Diamox is an OAT3 inhibitor and our reader Agnieszka found it beneficial only when administered along with Bumetanide.
Strong coffee is an OAT3 inhibitor and this was found to enhance bumetanide by Petra’s son with Asperger’s.
Cinnamon which contains epicatechin, another OAT3 inhibitor, did seem to be helpful in Monty who also takes bumetanide.
I suspect Diamox may be the most potent OAT3 inhibitor of those three
The interesting OAT3 inhibitors seem to be:-

·        Probenecid

·        Low dose aspirin

·        Epicatechin (cocoa, cinnamon ..)

·        Chlorogenic acids (coffee and decaffeinated green coffee extracts) 

Cinnamon, high flavanol cocoa and indeed coffee (minus the caffeine) have numerous health benefits.
Note that Catechin has no effect on OAT3. EGCG was not tested but in other studies has been shown it does affect.



The logical next step would be to improve bumetanide transport across the blood brain barrier.










Tuesday 14 March 2017

Leptin Signaling and JAK Inhibitors in Early Onset Autism - perhaps RORα and Adiponectin?


A future baldness therapy (a JAK inhibitor) to treat some autism?

Today’s rambling post has been pending for some time. It got left on one side, but is interesting and can be applied.
As we know there are distinct sub-types of autism and fortunately so does Paul Ashwood at the UC Davis MIND Institute. He often splits his findings into regressive vs early onset autism. 


There is evidence of both immune dysregulation and autoimmune phenomena in children with autism spectrum disorders (ASD). We examined the hormone/cytokine leptin in 70 children diagnosed with autism (including 37 with regression) compared with 99 age-matched controls including 50 typically developing (TD) controls, 26 siblings without autism, and 23 children with developmental disabilities (DD). Children with autism had significantly higher plasma leptin levels compared with TD controls (p<.006). When further sub-classified into regression or early onset autism, children with early onset autism had significantly higher plasma leptin levels compared with children with regressive autism (p<.042), TD controls (p<.0015), and DD controls (p<.004). We demonstrated an increase in leptin levels in autism, a finding driven by the early onset group.

A second study also found elevated leptin levels. 


Results: We found decreased levels of resistin, increased levels of leptin and unaltered levels of adiponectin in plasma from ASD subjects in comparison with controls. There was also a negative correlation between the levels of adiponectin and the severity of symptoms as assessed by the SRS. Conclusion: There are significant changes in the plasma levels of adipokines from patients with ASDs. They suggest the occurrence of systemic changes in ASD and may be hallmarks of the disease.


So today's post is really investigating what high levels of leptin in early onset autism might mean.  Is this just another abnormality produced by autism, or is it something to be fixed?  It appears to be the latter.



In my simplification of classic autism one of my four broad categories is neuroinflammation. These four categories interrelate, so a problem with one may affect all four. There are all kinds of mechanisms involved in chronic inflammation and this is why there are so many types of treatment for arthritis, IBS, IBD etc.
Recall all those posts about the activated microglia, the brain’s main form of active immune defence, and how in autism the body’s “immunostat” is somehow stuck on maximum.
So there is a long list of immune-modulating therapies that might help autism.  There is already a long list for conditions like arthritis. 
What works wonders for a few, like the TSO parasite worms, fails to help the majority when a larger clinical trial is carried out. 
One mechanism involved in the immune response is leptin signaling, the subject of today’s post.
It should be most relevant to people with unusually high levels of leptin that includes obese people and people with early onset autism.
So we have a hormone (leptin) driving inflammation. We saw in an earlier post how an imbalance in testosterone/estrogen connects with an ion channel dysfunction (KCC2/NKCC1) via ROR. So the hormone dysfunction is making the channelopathy worse.  Not so surprisingly we will see how high leptin associates with high testosterone (and hence low aromatase/estrogen).  The α4 subunit of ROR appears to drive leptin production.
We then have the choice of blocking the negative effects of high levels of leptin or we can go back to RORα and again consider treating autism like aromatase deficiency.  Aromatase is the enzyme that converts testosterone to estrogen in males.


We saw in autism a lack of estrogen receptors and a lack of aromatase, this then resulted in a lack of the neuroprotective effects of estrogen, which protects females from developing autism.
So if we increase estradiol not only do we  affect neurolin2 to produce more KCC2 and so lower intracellular chloride, but via  RORα we should produce less leptin in adipose (body fat) tissue.

Option A
Use JAK inhibitors to block the negative inflammatory effect of excess leptin.  There are potent inhibitors approved for arthritis and it looks like milder ones will be approved for treating some kinds of hair loss.

Option B
Deal with the proposed Purkinje-RORa-Estradiol-Neuroligin-KCC2 axis, by increasing estradiol and hope that via RORα, and more precisely RORα4, leptin levels reduce.
We know that high testosterone is associated with high leptin.
Since we want to solve as many of the damaging abnormalities found in autism, using the smallest number of therapies, Option B seems attractive.


Option C
Use a drug that reduces leptin.
Some PPAR gamma agonists are known to reduce leptin, including the thiazolidinedione Rosiglitazone. Some others do not.
PPAR gamma agonists have been used in autism for other reasons.

A natural PPAR gamma agonist is tangeritin/sytrinol.
There is a relationship between PPAR and RORα that is not yet understood in the literature.
Some readers of this blog are already using Option C.

Option D
Use a drug that raises adiponectin. Adiponectin is another hormone made in your fat cells and it reduces leptin. In some studies, low levels of Adiponectin are found in autism and that is not good for your wider health.
There is naturally some overlap with the therapies in option C.
Ways known to increase Adiponectin include:-

·        PPAR-γ agonists like rosiglitazone

·        PPAR- α agonists, like fibrates

·        ACE inhibitors, like Trandolapril

·        some statins (not simvastatin)

·        Niacin

·        renin-angiotensin-aldosterone system blockers

·        some calcium channel blockers, like Verapamil

·        mineralocorticoid receptor blockers,

·        new β-blockers

·        vanadyl sulfate (VS)

·        natural compounds; resveratrol has a modest effect, also reported in research are curcumin, capsaicin, gingerol, and catechins
  
What is Leptin?
Leptin is the satiety hormone and ghrelin is the hunger hormone.  They act together to regulate appetite.  In obese people leptin resistance occurs and they become desensitized to leptin.
People with obesity tend to have high levels of leptin, but it does them no good.
Unfortunately leptin has other functions unrelated to regulating how much you eat.  This is another example of evolution reusing the same substance for entirely different purposes.

Leptin plays a key role in the immune system and the regulation of the inflammatory response.
Leptin is a member of the cytokine superfamily and resembles IL-6, Autism’s public enemy #1. 
Chronically elevated leptin levels are associated not only with obesity but inflammation-related diseases, including hypertension, metabolic syndrome, and cardiovascular disease.   It is speculated that leptin responds specifically to adipose (body fat) derived inflammation.  Adipose tissue (body fat) produces hormones such as leptin, estrogen, resistin, and the cytokine TNFα.
Leptin also affects the HPA axis, which regulates the interactions among three endocrine glands, the hypothalamus, the pituitary gland and the adrenal.
The HPA axis is involved in the neurobiology of mood disorders and functional illnesses, including anxiety disorder, bipolar disorder, insomnia, post-traumatic stress disorder, borderline personality disorder, ADHD, major depressive disorder, burnout, chronic fatigue syndrome, fibromyalgia, irritable bowel syndrome, and alcoholism  

Leptin and testosterone levels? 

This study demonstrates a close association between serum levels of testosterone and leptin in males which has not been described previously. Serum testosterone levels could be an important contributor to the known gender difference in serum leptin levels which can be found even after correction for body composition.

The Leptin-JAK-STAT pathway
We can now jump forward in sophistication to the Leptin-JAK-STAT pathway.  This is the signaling pathway that lies behind much of what is going on with leptin.  It explains the comorbidities that people with high leptin may experience.
The pathway only makes full sense if you know a bit about the relevance of things like PKC, AKT etc. These pathways underlie how your body is regulated.  They are mainly being studied to understand all the types of cancer, but are equally relevant to the molecular understanding of autism. 
Tamoxifen, recently shown to reverse autism in a SHANK3 mouse model, is a PKC inhibitor. Aberrant loss or gain of Akt activation underlies the pathophysiological properties of a variety of complex diseases, including type 2 diabetes and cancer. PKC (and PKA) are reduced in regressive autism.

In general terms the Leptin-JAK-STAT pathway leads to inflammation and so it is a target for therapies to treat inflammatory disease like arthritis on inflammatory bowel disease.
You can reduce leptin signaling by inhibiting JAK.





After leptin binds to the long isoform of the leptin receptor (OB-Rb), Jak2 is activated at the box1 motif, resulting in the autophosphorylation of tyrosine residues and phosphorylation of tyrosines that provide docking sites for signaling proteins containing src homology 2 (SH2) domains. The autophosphorylated Jak2 at the box 1 motif can phosphorylate insulin receptor substrate1/2 (IRS1/2) that leads to activation of phosphatidylinositol 3-kinase (PI3K)/Akt pathway. Akt can regulate a wide range of targets including FOXO1 and NF-κB. Activation of NF-κB after leptin binding has been shown to induce Bcl-2 and Bcl-XL expressions. Leptin binding to OB-Rb can also activate the phospholipase C (PLC) for stimulation of c-jun N-terminal protein kinase (JNK) via protein kinase C (PKC).

Both Tyr1077 and Tyr1138 bind to STAT5, whereas only Tyr1138 recruits STAT1 and STAT3. STAT3 proteins form dimers and translocate to the nucleus to induce expression of genes such as c-fos, c-jun, egr-1, activator protein-1 (AP-1) and suppressors of cytokine signaling 3 (SOCS3). SOCS3 negatively regulates signal transduction by leptin by binding to phosphorylated tyrosines on the receptor, to inhibit the binding of STAT proteins and the SH2 domain-containing phosphatase 2 (SHP2). SHP2 activates the mitogen-activated protein kinase (MAPK) pathways including extracellular signal-regulated kinase (ERK1/2), p38 MAPK and p42/44 MAPK through an interaction with the adaptor protein growth factor receptor-bound protein 2 (GRB2), to induce cytokine and chemokine expression in immune cells. SOCS2 binds to Tyr1077 and might interfere with STAT5 binding. After stimulation with leptin, Src associated in mitosis protein 68 (Sam68) can form a complex with activated STAT3, leading to its dissociation from RNA. Sam68 can also be directly activated by Jak2 to phosphorylate IRS1/2 for Akt activation.



Leptin is a hormone whose central role is to regulate endocrine functions and to control energy expenditure. After the discovery that leptin can also have pro-inflammatory effects, several studies have tried to address - at the molecular level - the pathways involved in leptin-induced modulation of the immune functions in normal and pathologic conditions. The signaling events influenced by leptin after its binding to the leptin receptor have been under scrutiny in the past few years, and considerable experimental work has elucidated the consequences of leptin effects on immune cells. This review examines the biochemistry, function and regulation of leptin signaling in view of possible intervention on this molecule for a better management and therapy of immune-mediated diseases.


Janus kinase inhibitors/ JAK inhibitors
Janus kinase inhibitors, also known as JAK inhibitors inhibit the activity of one or more of the Janus kinase family of enzymes (JAK1, JAK2, JAK3, TYK2), thereby interfering with the JAK-STAT signaling pathway
The currently approved drugs are:-
  • Ruxolitinib against JAK1/JAK2 for psoriasis, myelofibrosis, and rheumatoid arthritis.
  • Tofacitinib against JAK3 for psoriasis and rheumatoid arthritis.
  •  Oclacitinib against JAK1 for the control of pruritus associated with allergic dermatitis and the control of atopic dermatitis in dogs

Both aspirin and Metformin have some related effects, but do not appear to be JAK inhibitors. 



JAK inhibitors for baldness?

Much of modern medicine is stumbled upon.  This has happened at least twice in the search for treatments for hair loss.  Merck developed Proscar based on the observation of a tribe that never had enlarged prostates, and then they found their new drug caused hair growth as a side effect, so they marketed a low dose version as Prospecia. Researchers at Columbia were treating a man with psoriasis using the JAK inhibitor Tofacitinib. He regrew a full head of hair within seven months.  He had a type of hair loss called Alopecia Areata.
Since haircare is a huge business, new JAK inhibitors are being developed for hair loss, both oral and topical.
Perhaps less potent JAK inhibitors than used for arthritis may be enough for people with autism and high leptin?


Natural JAK Inhibitors
We can also look in nature for potential JAK inhibitors.
By chance, before deciding to complete this post that been unfinished, I did look at some other unfinished once.  One that was all about the medicinal benefits of Nigella sativa, often called black cumin.
At least one reader of this blog is already a fan of Nigella sativa.
It turns out that one constituent of Nigella sativa is Thymoquinone. We know that Thymoquinone affects STAT3 in the complicated diagram above.  It is known to have anti-inflammatory and anticancer properties, but does it affect higher up the pathway at JAK?
For example, another natural product Cucurbitacin B, used in Chinese herbal medicine, is a dual inhibitor of the activation of both JAK2 and STAT3.
Brevilin A, a novel natural product, inhibits Janus Kinase Activity and blocks STAT3 Signaling. 






Back to Option B - RORα 


Here we show that gene expression of the nuclear receptor RORalpha is induced during adipogenesis, with RORalpha4 being the most abundantly expressed isoform in human and murine adipose tissue. Over-expression of RORalpha4 in 3T3-L1 cells impairs adipogenesis as shown by the decreased expression of adipogenic markers and lipid accumulation, accompanied by decreased free fatty acid and glucose uptake. By contrast, mouse embryonic fibroblasts from staggerer mice, which carry a mutation in the RORalpha gene, differentiate more efficiently into mature adipocytes compared to wild-type cells, a phenotype which is reversed by ectopic RORalpha4 restoration.

Previous studies have identified a role for RORa in cerebellum development, immune function and circadian rhythmicity. Recent reports have also outlined a function for RORa in cholesterol and lipid metabolism. In the present study we show that the RORa1 and RORa4 genes are expressed in adipose tissue and that RORa increases upon differentiation of preadipocytes into adipocytes, identifying RORa4 as the principal isoform in adipose tissue. Moreover, RORa4 over-expression in 3T3-L1 cells inhibits adipocyte differentiation, impairs fatty acid and glucose uptake and reduces expression of genes known to be involved in both adipocyte differentiation (including PPARc, CEBPa and aP2) and function (such as FAS, PEPCK, and the fatty acid and glucose transporters FATP, CD36 and Glut-4).

Although our experiments did not address the molecular mechanism(s) involved in the RORa-mediated inhibition of adipogenesis, several hypotheses can be put forward. Inhibition of adipocyte differentiation may occur principally through inhibition of positive regulators such as PPARc or CEBPa, or through the induction of inhibitory factors like GATA, KLF2, CHOP or Wnt signaling [3]. Alternatively, RORa may regulate other factors known

to inhibit adipocyte differentiation, for instance, through induction of p21CYP1/Waf1 leading to growth arrest. Along this line, Rev-erba acts as a p21 repressor in hepatic cells [27], and RORc induces p21 in liver. Thus, RORa might act, at least in part, by up-regulating p21 transcription in adipose cells. Another possible explanation may lie in the recent observation that Rev-erba represses PPARc2 gene expression during adipocyte differentiation [6]. The fact that RORa induces Rev-erba gene transcription ([28] and this report, not shown) may constitute an additional potential mechanism for adipogenesis inhibition by RORa.

Although future studies are necessary to further delineate RORa-regulated pathways in adipose cells, our findings clearly identify RORa4 as novel negative modulator of adipocyte differentiation and function.



Option C – reduce Leptin

Thiazolidinediones/glitazones
Thiazolidinediones also known as glitazones, are a class of medications used in the treatment of diabetes mellitus type 2.

Thiazolidinediones act by activating PPARs (peroxisome proliferator-activated receptors with greatest specificity for PPARγ.
Chemically, the members of this class are derivatives of the parent compound thiazolidinedione, and include:


PPARgamma agonist have been trialed with some success in autism.


These results indicate that antidiabetic thiazolidinediones down-regulate leptin gene expression with potencies that correlate with their abilities to bind and activate PPARgamma.


The thiazolidinedione BRL 49653 and the thiazolidinedione derivative CGP 52608 are lead compounds of two pharmacologically different classes of compounds. BRL 49653 is a high affinity ligand of peroxisome proliferator-activated receptor gamma (PPARgamma) and a prototype of novel antidiabetic agents, whereas CGP 52608 activates retinoic acid receptor-related orphan receptor alpha (RORA) and exhibits potent antiarthritic activity. Both receptors belong to the superfamily of nuclear receptors and are structurally related transcription factors. We tested BRL 49653 and CGP 52608 for receptor specificity on PPARgamma, RORA, and retinoic acid receptor alpha, a closely related receptor to RORA, and compared their pharmacological properties in in vitro and in vivo models in which these compounds have shown typical effects. BRL 49653 specifically induced PPARgamma-mediated gene activation, whereas CGP 52608 specifically activated RORA in transiently transfected cells. Both compounds were active in nanomolar concentrations. Leptin production in differentiated adipocytes was inhibited by nanomolar concentrations of BRL 49653 but not by CGP 52608. BRL 49653 antagonized weight loss, elevated blood glucose levels, and elevated plasma triglyceride levels in an in vivo model of glucocorticoid-induced insulin resistance in rats, whereas CGP 52608 exhibited steroid-like effects on triglyceride levels and body weight in this model. In contrast, potent antiarthritic activity in rat adjuvant arthritis was shown for CGP 52608, whereas BRL 49653 was nearly inactive. Our results support the concept that transcriptional control mechanisms via the nuclear receptors PPARgamma and RORA are responsible at least in part for the different pharmacological properties of BRL 49653 and CGP 52608. Both compounds are prototypes of interesting novel therapeutic agents for the treatment of non-insulin-dependent diabetes mellitus and rheumatoid arthritis.

BRL-49653 became the drug Rosiglitazone
CGP 52608 was not commercialized.



In our study, activation of PPAR𝛾 also negatively regulates leptin signaling. PPAR𝛾 and its agonist ciglitazone downregulate leptin, and its receptor mRNA expression, inhibit leptin-induced STAT3 phosphorylation and activation and increase STAT3 inhibitor SOCS3 expression. These findings indicate that PPAR𝛾 and leptin signaling pathways are mutually regulated in growth plate chondrocytes. The imbalance between the levels of PPAR𝛾 and leptin may facilitate the dysfunction of the growth plate observed in obese children.


Option D – Increase Adiponectin

Adiponectin restrains leptin-induced signalling

Another hormone you may not of heard of is Adiponectin; is it secreted from the same adipose tissue that produces leptin.
Whereas the high levels of leptin found in classic autism appear to be bad for you, it is the low levels of Adiponectin found in autism, and indeed ADHD, that may be bad for. Low levels of Adiponectin are associated with many conditions ranging from NAFLD to type 2 diabetes.
Another way to reduce leptin signaling is to increase the level of Adiponectin.
Much is known about ways to increase adiponectin and many readers of this blog are actually already doing it. Ways to increase it include:-

·        PPAR-γ agonists like rosiglitazone

·        PPAR- α agonists, like fibrates

·        ACE inhibitors, like Trandolapril

·        some statins (not simvastatin)

·        Niacin

·        renin-angiotensin-aldosterone system blockers

·        some calcium channel blockers, like Verapamil

·        mineralocorticoid receptor blockers,

·        new β-blockers

·        vanadyl sulfate (VS)

·        natural compounds; resveratrol has a modest effect, also reported in research are curcumin, capsaicin, gingerol, and catechins
Combining an ACE inhibitor with the calcium channel blocker verapamil has an even bigger effect on Adiponectin levels.


Reduced levels of adiponectin are found in some Autism studies  


The neurobiological basis for autism remains poorly understood. We hypothesized that adipokines, such as adiponectin, may play a role in the pathophysiology of autism. In this study, we examined whether serum levels of adiponectin are altered in subjects with autism. We measured serum levels of adiponectin in male subjects with autism (n = 31) and age-matched healthy male subjects (n = 31). The serum levels of adiponectin in the subjects with autism were significantly lower than that of normal control subjects. The serum adiponectin levels in the subjects with autism were negatively correlated with their domain A scores in the Autism Diagnostic Interview—Revised, which reflects their impairments in social interaction. This study suggests that decreased levels of serum adiponectin might be implicated in the pathophysiology of autism.  

Autism is a neurodevelopmental disorder with pathogenesis not completely understood. Although a genetic origin has been recognized, it has been hypothesized a role for environmental factors, immune dysfunctions, and alterations of neurotransmitter systems. In young autistic patients we investigated plasma leptin and adiponectin levels over a year period. Thirty-five patients, mean age at the basal time 14.1 ± 5.4 years, were enrolled. Controls were 35 healthy subjects, sex and age matched. Blood samples were withdrawn in the morning at the baseline and 1 year after. In patients leptin concentrations significantly increased, while adiponectin did not significantly change. Leptin values in patients were significantly higher than those found in controls at each time; adiponectin values did not differ at each time between patients and controls. Since patients were not obese, we could hypothesize that leptin might participate to clinical manifestations other than weight balance. The role of adiponectin in autism is still debatable.


Modulation of adiponectin as therapy
In many conditions it is already considered wise to modulate adiponectin as a therapy.  Examples are diabetes and cardiovascular disease.  The subject is quite well studied.

Adiponectin is produced predominantly by adipocytes and plays an important role in metabolic and cardiovascular homeostasis through its insulin-sensitizing actions and anti-inflammatory and anti-atherogenic properties. Recently, it has been observed that lower levels of adiponectin can substantially increase the risk of developing type 2 diabetes, metabolic syndrome, atherosclerosis, and cardiovascular disease in patients who are obese. Circulating adiponectin levels are inversely related to the inflammatory process, oxidative stress, and metabolic dysregulation. Intensive lifestyle modifications and pharmacologic agents, including peroxisome proliferator-activated receptor-γ or α agonists, some statins, renin-angiotensin-aldosterone system blockers, some calcium channel blockers, mineralocorticoid receptor blockers, new β-blockers, and several natural compounds can increase adiponectin levels and suppress or prevent disease initiation or progression, respectively, in cardiovascular and metabolic disorders. Therefore, it is important for investigators to have a thorough understanding of the interventions that can modulate adiponectin. Such knowledge may lead to new therapeutic approaches for diseases such as type 2 diabetes, metabolic syndrome, cardiovascular disease, and obesity. This review focuses on recent updates regarding therapeutic interventions that might modulate adiponectin.

  
The Secretome of human adipose tissue

The genome, the epigenome and the microbiome, we now have the secretome. Human body fat is an endrocrine organ producing more than 600 different proteins; the first one, leptin, was identified only in 1994.

Adipokines: A treasure trove for the discovery of biomarkers for metabolic disorders

So clearly scientists have a very long way to go to understand how the human body works.




Conclusion
It is odd how in this blog we keep coming back to drugs that are helpful for diabetes and high cholesterol. Obesity also recurs as a theme.
Interesting present day options seem to be:-
·        JAK inhibitors (Ruxolitinib, Tofacitinib)

·        Estradiol, my hunch with some evidence

·        PPAR gamma agonists Rosiglitazone (Avandia) or lots of Tangeretin/Sytrinol

·        ACE inhibitors, some statins, verapamil, fibrates and niacin 

I think some people will benefit from the following, but perhaps not due reduced leptin signaling

·        Low dose aspirin

·        Metformin, in human use for more than 50 years to treat type 2 diabetes the molecular mechanism of metformin is incompletely understood

·        Nigella sativa / Thymoquinone