Seabuckthorn Leaves Increase PPAR-Alpha & PPAR-Gamma Expression, Keep the Liver Fat Free and Fatty Oxidation Up. Plus: PPARs - High or Low? How Are They Supposed to Be?

This time, the magic is in the leaves, not the fruits or kernels. And it's dose dependent. With an almost linear increase from 500-1,000mg/kg

Honestly, I don't think that it is coincidence that many of the most promising medical plants are shrubs that live on barren soil, like sand dunes and cliffs and are full of thorns as well as innate polyphenolic defense mechanisms. Whatever the "evolutionary" basis may be, if we go by the beneficial metabolic effects, researchers from the Department of Food Science and Human Nutrition at the Chonbuk National University in the Republic of Korea, it appears worth going through all the traditional used folk medicine across the world and identify which of them work, how they work and whether they may already have what it takes to get rid of one or the other of the typical Western diseases.

In the case of the ethanolic extract of seabuckthorn (Hippophae rhamnoides L) Pichiah et al. used in their most recent experiment, this would be ameliorative effects on weight gain through down-regulation of adipogenic and lipogenic gene expression.

Less weight gain more fatty acid turnover, better glucose management and leptin sensitivity

The ameliorative effects on the detoriation of glucose metabolism, the reduced but still significant weight gain of the 60% fat diet (additional fat 100% from lard) and the profound overexpression of leptin, which is indicative of the fact that the mice developed full-blown leptin resistance within the 13-weeks of HFD administration, were all ameliorated to a greater degree in the high dose seabuckthorn leaf extract group (human equivalent  ~6.5g/day).

Figure 1: Effect of the different diets on weight gain, visceral fat weight, feed intake and energy intake (left; data expressed relative to control diet); effects on blood sugar (AUC in glucose tolerance test) and leptin (Pichiah. 2012)

The differences between high and low dose supplementation of the extract which had been prepared by

"[...] by soaking the dried, powdered leaves in 70% ethanol for 7 days at room temperature. Then the extract was concentrated by evaporating ethanol using a rotary vacuum evaporator (N-N Series, EYELA, Tokyo, JAPAN) set at 60°C and 100 hPa" (Pichiah. 2012)

were even more pronounced, when we compare the effects on fatty acid oxidation (CPT-1), the PPAR-alpha and -gamma values.

Figure 2: Carnitine palmitoyltransferase I (CPT1), PPAR-alpha & -gamma activity and triglyceride & cholesterol content in the liver (left; expressed relative to rodents on normal chow). Histology of liver sections at 200x magnification for the different diets (Pichiah. 2012)

What's yet most striking is however that the liver - the organ that's so heavily involved in the etiology of insulin resistance - was virtually "fat-free" in the rodents who received the 1,000mg/day dose. The total triglyceride and cholesterol content was even lower than in the mice on the normal diet and the overall darker staining in the slices on the right of figure 2 is only further evidence of the beneficial effects the seabuckthorn extract had on the liver histology.

The effects of a 5% conjugated linoleic acid diet do actually resemble that of lipodystrophy, i.e. pathological fat loss and inability to store body fat. Strange, no? Well that's PPAR-gamma (read more).

PPAR-gamma? Wasn't that what you actually wanted to avoid? In a way this is right, since PPAR-gamma and even alpha are somewhat Janus-faced molecules (overview for PPAR-alpha). As beneficial as their expression in the liver may be, both inhibit the oxidation of glucose. PPAR-gamma is also involved in the maturation process from pre-adipocytes to mature adipocytes, increases lipogenesis in white adipose tissues, decreases the cell surface fatty acid transporter on muscle cells and increases glucose uptake in adipocytes (exclusively). All that is healthier than fat clogging your liver, but it's not exactly something that will make you leaner if you are work out and consume a junk-free diet.

In fact, the PPAR-gamma suppressing effects of the trans-10, cis-12 isomer of conjugated linoleic acid (CLA; cf. Kennedy. 2008) are actually what what produces such profound effects, as they were observed in the study I discussed on July 22, 2012 (see link beneath the image of the mice).

TTA and fish oil are potent antagonists of liver PPAR expression. With the uncoupling and anti-inflammatory effects of TTA being the key to unleash & maintain fat-burning (read more).

Bottom line: It appears as if the liver is - once again - emerging as a central player in "sick obesity", meaning being fat and sick and not just fat. Which reminds me of yesterday's post on Gluten and the development of metabolic disease, where fatness is no criteria, at all. The expression of the "liver cleansing" PPAR-gamma enzymes on the other hand was.

This in turn reminds me of the effects of fish oil and TTA (a pan PPAR-activator), which - despite their questionable use as a long-term intervention can in fact stimulate intra-hepatic fatty acid oxidation to levels which are so high that oxidation rates in and out of itself could bring about some problems.

Other nutritional factors you should take into account are choline (a deficiency will actually cause fatty liver disease; read more about choline) or taurine. And on the endocrine side of things you want to keep an eye on optimal DHEA levels (read more about its effects on PPAR-gamma), thyroid hormones, testosterone and estrogen (Nemoto. 2000).

References

• Kennedy A, Chung S, LaPoint K, Fabiyi O, McIntosh MK. Trans-10, cis-12 conjugated linoleic acid antagonizes ligand-dependent PPARgamma activity in primary cultures of human adipocytes. J Nutr. 2008 Mar;138(3):455-61.
• Nemoto Y, Toda K, Ono M, Fujikawa-Adachi K, Saibara T, Onishi S, Enzan H, Okada T, Shizuta Y. Altered expression of fatty acid-metabolizing enzymes in aromatase-deficient mice. J Clin Invest. 2000 Jun;105(12):1819-25.
• Pichiah PB, Moon HJ, Park JE, Moon YJ, Cha YS. Ethanolic extract of seabuckthorn (Hippophae rhamnoides L) prevents high-fat diet-induced obesity in mice through down-regulation of adipogenic and lipogenic gene expression. Nutr Res. 2012 Nov;32(11):856-64.

Beyond Celiac: Study Sheds New Light on Obesogenic Effects of Gluten - Are PPARs & Bacteria Both Involved?

Cornflakes peanut butter cookies - guaranteed not gluten free ;-)

With Christmas Eve being over, and grandma's cookies, Christmas stollen, and all sorts of other stuff from the bakery in front of you (literally), Christmas Day may actually prove to be a way more "dangerous" than Christmas Eve - not just because of the total amount of calories, but also because of the low satiety effect of these sweet treats.

A recent paper by scientists from the Universidade Federal de Minas Gerais in Belo Horizonte in Brazil does now point to another reason you better give those bakery products a wide berth - not just, but especially with the energy overshoot on Christmas day: Gluten!

Study confirms for the first time what scientists and laymen alike have been speculating about

In what the scientists claim is the first well-controlled study of the effects of gluten intake on metabolic health in a non-celiac, but Western-style diet scenario, Fabíola Lacerda Pires Soares and her colleagues put two groups of C57BL/6 mice on identical, iso-caloric high fat (hypercaloric) diets that differed only in terms of the amount of gluten that was added to the chow (0% gluten vs. 4.5% gluten).

Interestingly, the gluten diet did not influence any of the usual suspects, like food intake, total fat-free mass, fecal lipids excretion, blood lipid profile, blood total protein and ectopic (liver and muscle) lipid concentration (if you look closely you will realize that the gluten-free group actually had higher TRIGs, although the difference did not reach statistical significance).

Figure 1: Usual suspects and closer look at the effects 8 weeks gluten supplemented vs. gluten-free diets had on serum markers of metabolic syndrome and visceral fat parameters (Soares. 2012)

The data in figure 1 (right) does yet also show that the gluten content of the diet did nevertheless have a significant impact on the total body mass, visceral fat mass, lipid content and most importantly the adipocyte size.

Figure 2: Absolute adipokine levels (left) and fasting glucose and insulin levels, as well as Homa-IR (Soares. 2012)

Add to that the blunted expression of the anti-inflammatory and anti-diabetic fat hormone adiponectin and the increased the >5x higher expression of leptin (figure 2). And mix that with the reduced expression of PPAR-alpha and gamma of which Soares et al. argue that they may well be the key factor in the detrimental modulatory effect the addition of gluten had on the visceral fat structure and the lowered expression of the fat liberating enzymes LPL and and HSL, as well as reduced levels of the fat burning proteins ACC and CPT-1 (figure 3).

Figure 3: PPAR-alpha, -gamma, LPL, HSL, ACC and CPT-1 expression compared to rodents on regular chow (left); crown like structures in stained slices from visceral fat, inflammatory markers TNF-alpha and IL-6 (Soares. 2012)

So, even if the initially mentioned blood markers (aka the usual suspects) would suggest that both the gluten-consuming and gluten-free rodents were similarly bad off, the profound difference in inflammatory markers within the adipose tissue and the presence of comparatively many necrotic and inflammatory adipocytes in the crown like structures stand in line with increases in HOMA-IR, fasting glucose and insulin and an already compromised glucose clearance which are well-known harbingers of the metabolic syndrome.

These observations do not simply shed a whole new light on a hitherto largely ignored contributer to the etiology of the metabolic syndrome, they do also show that one of the reasons it has not been identified before is an over-reliance on BMI, total fat mass and serum lipids in the early stages of diabesity.

Reardless of whether the gut microbiome is part of the mechanism by which gluten predisposes the development of metabolic syndrome. Eating more inulin- and beta-glucan rich foods like Jerusalem artichokes, agave, bananas, onion, steel cut oats, wild yams, yacon, etc. certainly won't hurt your efforts to get lean, stay lean and leave the role of the obese diabetic to the other (read more)

Bottom line: The study at hand provides a good reason to limit your intake of "healthy whole grains" and other gluten containing foods, regardless of whether you suffer from celiac or not. Whether the established detrimental effects of gluten on the integrity of the intestinal wall and the increased leakage of bacterially produced endotoxins from the highly unfavorably changes in the gut microbiome in response to the high fat diets (Hildebrandt. 2009) are part of, or even the primary cause of these observations still has to be elucidated. The same goes for strategies to counter the translocation of the endotoxins across the gut lining (cf. "Shedding some light on the leaky gut") and the dose response relationship between the total amount of gluten in your diet and its effects on your metabolism. With 7% of pure gluten, it goes without saying that you would basically have to live of wheat in order to get to anywhere similar amounts of gluten in the diet... that said: Is it possible that the effects occur only in the presence of the high fat diet? After all, this alone has been shown to favor a pro-inflammatory gut microbiome.

You see there are enough questions to be answered in 2013 and the SuppVersity is going to be the place you will read the respective answers first ;-)

References:

• Hildebrandt MA, Hoffmann C, Sherrill-Mix SA, Keilbaugh SA, Hamady M, Chen YY, Knight R, Ahima RS, Bushman F, Wu GD. High-fat diet determines the composition of the murine gut microbiome independently of obesity. Gastroenterology. 2009 Nov;137(5):1716-24.e1-2.
• Soares FL, de Oliveira Matoso R, Teixeira LG, Menezes Z, Pereira SS, Alves AC, Batista NV, de Faria AM, Cara DC, Ferreira AV, Alvarez-Leite JI. Gluten-free diet reduces adiposity, inflammation and insulin resistance associated with the induction of PPAR-alpha and PPAR-gamma expression. J Nutr Biochem. 2012 Dec 17.

Conjugated Linoleic Acids: What's the Difference Between cis-9,11 and trans-10,12 CLA and Should We Label Them as "Transfats"? Plus: What Makes CLA Potentially Harmful?

If Hayden Panettiere drinks it dairy can't be bad - despite (or because?) CLA, right? Well, what if I told you that Mrs. Panettiere was advertising milk in the "Got Milk" campaign despite being lactose intolerant?

As a SuppVersity veteran you will be familiar with the idea that trans-10, trans-12 conjugated linoleic acid is the "fat burning" CLA isomer, while 9 cis,11 trans linoleic acid appears to blunt some of the pro-inflammatory actions of its cousin and has been shown to have specific physiological effects on it's own (e.g. increased bone health, cf. Platt. 2009; anti-cancer, cf. Corl. 2003).

As I already mentioned, this is probably nothing new for you, if you make sure to get your daily dose of SuppVersity wisdom everyday. What you may however not be aware of is the fact that researchers like Ye Wang and Spencer D. Proctor are - despite the never-ending hoopla around potential weight loss effects of CLA - still contemplating, whether CLA could not pose a major health threat to all or at least certain subgroups of the population and whether this should or shouldn't be reason enough to change the current food labeling practices.

Do we have to label CLA as "transfat"?

From a technical perspective the above question is obsolete. CLAs are transfats and would thus (technically, again) have to be labeled as such on the product label. From a health perspective, however, things do in fact look different. Due to the fact that the aforementioned ruminant (=naturally produced in the stomach(s) of ruminents) trans-fats have been associated with health benefits (Gebauer. 2011), we could effectively risk to scare consumers away from healthy foods if they were listed as part of the "transfat" category on the product labels.

What's actually the reason that one the same CLA isomer that will have you lose body fat will also "inflame" you? Due to the fact that most of the research on "fat loss supplements" is conducted in sick, obese individuals, people tend to get the false impression that "fat burners" were anti-inflammatory and that anti-inflammatory agents would burn fat.

Effects of 10-trans,12 CLA on fatty acids & glucose metabolism and IL-6 gene expression in isolated fat cells in the petri dish (Hartwig. 2013)

Now, while it is correct that soothing inflammation will help the future Mr. Average Joe, who is going to be an obese (pre-)diabetic, lose weight, this has little to do with any active contribution to the oxidation of body fat. 10-trans,12 CLA, on the other hand, has been shown to block lipid storage, increase mitochondrial uncoupling (UCP-2), lower PPAR-alpha and ramp up the oxidation and release of fatty acids from the fat stores (Hartig. 2013). Unfortunately it will also block the uptake of glucose and increase the expression of the pro-inflammatory cytokine IL-6 in fat cells. So, if you took 10-trans,12 CLA at very high doses it will probably in fact keep you lean.

If you cannot handle the sudden increase in free fatty acids, pack the glucose into your liver and muscle glycogen stores and deal with the exuberant amount of inflammatory cytokines, however, it will only make you sick.

Currently, the trans-fat content on many food labels (and in legislative documents) does not include ruminant CLA isomers and Wang and Procter acknowledge that:

"As highlighted in a recent quantitative review of prospective cohort studies by Bendsen et al. dietary consumption of ruminanttrans-fat may be protective against total as well as fatal CHD events." (Wang. 2013)

The researchers do however point out that concerns about potential adverse effect on atherogenic cholesterol profiles from supplemental CLA are not unwarranted - at least if they are used by a group of persons - abdominally obese and/or insulin resistant men, for example (Riserus. 2002 a,b).

Australia and New Zealand suggest a re-evaluation

Accordingly, Australia and New Zealand (FSANZ) proposed to re-evaluate their perception regarding the exclusion of CLA from the TFA definition on nutrition labels.

If you re-evaluate something, you do not necessarily have to change them and if you go through the concise summary of results Wang and Procter present in their paper (see table 1 for an overview of the currently published meta-analyses, it does not appear necessary to question the current practice to label only industrually produced trans fats.

Table 1: Meta analysis with beneficial (green), neutral (grey) and potentially negative outcome (red); based on Wang & Proctor (2013)

As the authors point out, the inclusion of CLA in the total amount of transfats on the label would only drive people away from the consumption of whole food products. This is particularly true in view of the fact that the ill-health effects of "trans-fats" are something everyone will have heard about. The fact that these ill health effects are not to be expected from trans fats in dairy and other CLA containing whole foods, on the other hand, is still news to many costumers.

Moreover, how would you, me and everyone else who may well be aware that CLAs are not the bad guys and the "trans-fat" in grass fat butter is not going to hurt us know if the 3g of transfats in another product we buy are actually from the undisclosed amount of butter (and thus CLA) in it? It could likewise be that the producer added a little extra partially hydrogenated vegetable oil to cut the product costs and neither you nor me would know that.

Suggested read: "A Higher Intake of CLA and Vaccenic Acid from Dairy, Beef, Veal and Lamp Could Prevent Subtle Weight Gain" | read more

Only the obese have to be worried: Based on the currently available evidence the healthy and lean person (hopefully you) has absolutely no reason to avoid products with a "high" natural CLA content and thus both the pro- (trans-10,12) and (partly) anti-inflammatory (cis-9,11) form of CLA in them.

For obese and insulin resistant individuals things do however look somewhat different. A 2004 study by Risérus et al., for example, has been able to show that even the allegedly "harmless", 9 cis,11 trans linoleic acid can worsen both lipid peroxidation and insulin resistance in 25 abdominally obese men. (Risérus. 2004).

With 3g/day the dosage that was used in the Risérus study, the amount of CLA was yet much hither than the amount of CLA you can possibly ingest with nourishing foods such as butter, full-fat dairy, grass-fed beef (and beef in general, by the way). Instead of these you are thus better advised to avoid CLA supplements... but don't worry if you take another look at the data in table 1 you will have to concede that they are pretty much useless, anyway.

Reference:

• Corl BA, Barbano DM, Bauman DE, Ip C. cis-9, trans-11 CLA derived endogenously from trans-11 18:1 reduces cancer risk in rats. J Nutr. 2003 Sep;133(9):2893-900.
• Gebauer SK, Chardigny JM, Jakobsen MU, et al. Effects of ruminanttrans fatty acids on cardiovascular disease and cancer: a comprehensive review of epidemiological, clinical, and mechanistic studies.Adv Nutr. 2011; 2, 332 – 354.
• den Hartigh LJ, Han CY, Wang S, Omer M, Chait A. 10E,12Z-conjugated linoleic acid impairs adipocyte triglyceride storage by enhancing fatty acid oxidation, lipolysis, and mitochondrial reactive oxygen species. J Lipid Res. 2013 Nov;54(11):2964-2978. 
• Lenz TL & Hamilton WR. Supplemental products used for weight loss. J Am Pharm Assoc. 2004; 44,  59– 67, quiz 67– 58.
• Onakpoya IJ, Posadzki PP, Watson LK, Davies LA, Ernst E. The efficacy of long-term conjugated linoleic acid (CLA) supplementation on body composition in overweight and obese individuals: a systematic review and meta-analysis of randomized clinical trials. Eur J Nutr. 2012 Mar;51(2):127-34.
• Platt I, El-Sohemy A. Effects of 9cis,11trans and 10trans,12cis CLA on osteoclast formation and activity from human CD14+ monocytes. Lipids Health Dis. 2009 Apr 29;8:15.
• Risérus U, Arner P, Brismar K, Vessby B. Treatment with dietary trans10cis12 conjugated linoleic acid causes isomer-specific insulin resistance in obese men with the metabolic syndrome. Diabetes Care. 2002 Sep;25(9):1516-21.
• Risérus U, Basu S, Jovinge S, Fredrikson GN, Arnlöv J, Vessby B. Supplementation with conjugated linoleic acid causes isomer-dependent oxidative stress and elevated C-reactive protein: a potential link to fatty acid-induced insulin resistance. Circulation. 2002 Oct 8;106(15):1925-9
• Salas-Salvadó J, Márquez-Sandoval F, Bulló M. Conjugated linoleic acid intake in humans: a systematic review focusing on its effect on body composition, glucose, and lipid metabolism. Crit Rev Food Sci Nutr. 2006;46(6):479-88. Review.
• Schoeller DA, Watras AC, Whigham LD. A meta-analysis of the effects of conjugated linoleic acid on fat-free mass in humans. Appl Physiol Nutr Metab. 2009 Oct;34(5):975-8.
• Tricon S, Yaqoob P. Conjugated linoleic acid and human health: a critical evaluation of the evidence. Curr Opin Clin Nutr Metab Care. 2006 Mar;9(2):105-10. Review.
• Whigham LD, Watras AC, Schoeller DA. Efficacy of conjugated linoleic acid for reducing fat mass: a meta-analysis in humans. Am J Clin Nutr. 2007 May;85(5):1203-11.