Indian National Association for Study of the Liver (INASL) Guidance Paper on Nomenclature, Diagnosis and Treatment of Nonalcoholic Fatty Liver Disease (NAFLD)

Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease globally and in India. The already high burden of NAFLD in India is expected to further increase in the future in parallel with the ongoing epidemics of obesity and type 2 diabetes mellitus. Given the high prevalence of NAFLD in the community, it is crucial to identify those at risk of progressive liver disease to streamline referral and guide proper management. Existing guidelines on NAFLD by various international societies fail to capture the entire landscape of NAFLD in India and are often difficult to incorporate in clinical practice due to fundamental differences in sociocultural aspects and health infrastructure available in India. A lot of progress has been made in the field of NAFLD in the 7 years since the initial position paper by the Indian National Association for the Study of Liver on NAFLD in 2015. Further, the ongoing debate on the nomenclature of NAFLD is creating undue confusion among clinical practitioners. The ensuing comprehensive review provides consensus-based, guidance statements on the nomenclature, diagnosis, and treatment of NAFLD that are practically implementable in the Indian setting.

Association of Cardiometabolic Disease With Cancer in the Community

Background

Obesity and cardiometabolic dysfunction have been associated with cancer risk and severity. Underlying mechanisms remain unclear.

Objectives

The aim of this study was to examine associations of obesity and related cardiometabolic traits with incident cancer.

Methods

FHS (Framingham Heart Study) and PREVEND (Prevention of Renal and Vascular End-Stage Disease) study participants without prevalent cancer were studied, examining associations of obesity, body mass index (BMI), waist circumference, visceral adipose tissue (VAT) and subcutaneous adipose tissue depots, and C-reactive protein (CRP) with future cancer in Cox models.

Results

Among 20,667 participants (mean age 50 years, 53% women), 2,619 cancer events were observed over a median follow-up duration of 15 years. Obesity was associated with increased risk for future gastrointestinal (HR: 1.30; 95% CI: 1.05-1.60), gynecologic (HR: 1.62; 95% CI: 1.08-2.45), and breast (HR: 1.32; 95% CI: 1.05-1.66) cancer and lower risk for lung cancer (HR: 0.62; 95% CI: 0.44-0.87). Similarly, waist circumference was associated with increased risk for overall, gastrointestinal, and gynecologic but not lung cancer. VAT but not subcutaneous adipose tissue was associated with risk for overall cancer (HR: 1.22; 95% CI: 1.05-1.43), lung cancer (HR: 1.92; 95% CI: 1.01-3.66), and melanoma (HR: 1.56; 95% CI: 1.02-2.38) independent of BMI. Last, higher CRP levels were associated with higher risk for overall, colorectal, and lung cancer (P < 0.05 for all).

Conclusions

Obesity and abdominal adiposity are associated with future risk for specific cancers (eg, gastrointestinal, gynecologic). Although obesity was associated with lower risk for lung cancer, greater VAT and CRP were associated with higher lung cancer risk after adjusting for BMI.

A higher-protein nut-based snack product suppresses glycaemia and decreases glycaemic response to co-ingested carbohydrate in an overweight prediabetic Asian Chinese cohort: the Tū Ora postprandial RCT

Nut-based products may aid low-glycaemic dietary strategies that are important for diabetes prevention in populations at increased risk of dysglycaemia, such as Asian Chinese. This randomised cross-over trial assessed the postprandial glycaemic response (0-120 min) of a higher-protein nut-based (HP-NB) snack formulation, in bar format (1009 kJ, Nutrient Profiling Score, NPS, -2), when compared with an iso-energetic higher-carbohydrate (CHO) cereal-based bar (HC-CB, 985 kJ, NPS +3). It also assessed the ability to suppress glucose response to a typical CHO-rich food (white bread, WB), when co-ingested. Ten overweight prediabetic Chinese adults (mean, sd: age 47⋅9, 15⋅7 years; BMI 25⋅5, 1⋅6 kg/m2), with total body fat plus ectopic pancreas and liver fat quantified using dual-energy X-ray absorptiometry and magnetic resonance imaging and spectroscopy, received the five meal treatments in random order: HP-NB, HC-CB, HP-NB + WB (50 g available CHO), HC-CB + WB and WB only. Compared with HC-CB, HP-NB induced a significantly lower 30-120 min glucose response (P < 0⋅05), with an approximately 10-fold lower incremental area under the glucose curve (iAUC0-120; P < 0⋅001). HP-NB also attenuated glucose response by approximately 25 % when co-ingested with WB (P < 0⋅05). Half of the cohort had elevated pancreas and/or liver fat, with 13-21 % greater suppression of iAUC0-120 glucose in the low v. high organ fat subgroups across all five treatments. A nut-based snack product may be a healthier alternative to an energy equivalent cereal-based product with evidence of both a lower postprandial glycaemic response and modulation of CHO-induced hyperglycaemia even in high-risk, overweight, pre-diabetic adults.

Weight-loss-independent benefits of exercise on liver steatosis and stiffness in Japanese men with NAFLD

Background & Aims

A weight-loss-independent beneficial effect of exercise on non-alcoholic fatty liver disease (NAFLD) management has been reported, but the underlying mechanism is unknown. To help determine this mechanism, the effects of exercise on individual tissues (liver, adipose tissue, and skeletal muscle) were retrospectively studied.

Methods

Data from Japanese obese men with NAFLD in a 3-month exercise regimen were analysed and compared with those in a 3-month dietary restriction program designed to achieve weight loss. The underlying mechanism was studied in a smaller subcohort.

Results

Independent of the effect of weight loss, the exercise regimen reduced liver steatosis by 9.5% and liver stiffness by 6.8% per 1% weight loss, and resulted in a 16.4% reduction in FibroScan-AST score. Improvements in these hepatic parameters were closely associated with anthropometric changes (reduction in adipose tissue and preservation of muscle mass), increases in muscle strength (+11.6%), reductions in inflammation and oxidative stress (ferritin: -22.3% and thiobarbituric acid: -12.3%), and changes in organokine concentrations (selenoprotein-P: -11.2%, follistatin: +17.1%, adiponectin: +8.9%, and myostatin: -21.6%) during the exercise regimen. Moreover, the expression of target genes of the transcription factor Nrf2, an oxidative stress sensor, was higher in monocytes, suggesting that Nrf2 is activated. Large amounts of high-intensity exercise were effective at further reducing liver steatosis and potentiating improvements in pathophysiological parameters (liver enzyme activities and organokine profiles).

Conclusions

The weight-loss-independent benefits of exercise include anti-steatotic and anti-stiffness effects in the livers of patients with NAFLD. These benefits seem to be acquired through the modification of inter-organ crosstalk, which is characterised by improvements in organokine imbalance and reductions in inflammation and oxidative stress.

Lay summary

We investigated the effects of exercise on non-alcoholic fatty liver disease (NAFLD) that were not related to weight loss. We found that exercise had considerable weight-loss-independent benefits for the liver through a number of mechanisms. This suggests that exercise is important for NAFLD patients, regardless of whether they lose weight.

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Exercise has effects on liver steatosis and stiffness, independent of weight loss.

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Exercise maintains muscle mass and alters the secretion of organokines.

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Exercise increases the phagocytic capacity of Kupffer cells and activates Nrf2.

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Exercise, especially vigorous exercise, should be used aggressively to manage non-alcoholic fatty liver disease (NAFLD).

Impact of maternal central adiposity on infant anthropometry and perinatal morbidity: A systematic review

Overweight and obesity during pregnancy are risk factors for a large number of perinatal complications, both for the mother and the infant. Risk stratification and early interventions are therefore highly clinically important to minimize future complications. Currently, body mass index (BMI) in early pregnancy is used for risk stratification of pregnant women, but a disadvantage of BMI is that it does not distinguish muscle from fat tissue and central from peripheral adiposity. Maternal fat distribution is suggested to be a better predictor than BMI of obesity-related adverse pregnancy outcomes, with central adiposity posing a greater risk than peripheral subcutaneous fat. With this study, we aimed to systematically review the evidence of what impact maternal central adiposity in early to mid-pregnancy or at most 365 days prior to conception has on infant anthropometry and perinatal morbidity.

The databases PubMed/MEDLINE, Web of Science Core Collection, CINAHL, SCOPUS, Clinical Trials, and Open Grey were searched from inception until November 2019. Eligible studies assessed the association between maternal central adiposity, in early to mid-pregnancy or at most 365 days prior to conception, and any of the following infant outcomes: preterm delivery (< 37 weeks of gestation), birthweight, macrosomia, large for gestational age, congenital malformations, hypoglycemia, hyperbilirubinemia, care at neonatal intensive care unit, and death. Two authors independently screened titles and abstracts, read the included full-text studies, and extracted data. The Newcastle-Ottawa Quality Assessment Scale for cohort studies was used to evaluate the quality of and risk of bias in the studies.

A total of 720 records were identified, 20 full-text studies assessed for eligibility, and 10 cohort studies included in the review. The results suggest that central adiposity in early to mid-pregnancy or at most 365 days prior to conception may contribute to increased birthweight and increased likelihood of delivery by cesarean section. There is also some evidence of associations between central adiposity and preterm delivery (< 37 weeks of gestation), and admission to neonatal intensive care unit. A meta-analysis was not possible to perform due to substantial heterogeneity among the included studies regarding the exposure, outcome, and statistical methods used.

Hence, central adiposity in early to mid-pregnancy or at most 365 days prior to conception could be a possible risk marker in addition to BMI for risk stratification of pregnant women. However, since the topic is only scarcely researched, and the results not unanimous, more studies are needed to further clarify the associations between maternal central adiposity and adverse neonatal complications, before any altered recommendations of guidelines could be made. To enable a future meta-analysis, studies using similar methods for central adiposity assessment,and similar outcome measures, are required.

Hepatic miR-192-3p reactivation alleviates steatosis by targeting glucocorticoid receptor

Background & Aims

The paradox of hepatic insulin resistance describes the inability for liver to respond to bioenergetics hormones in suppressing gluconeogenesis whilst maintaining lipid synthesis. Here, we report the deficiency of miR-192-3p in the livers of mice with diabetes and its role in alleviating hepatic steatosis.

Methods

As conventional pre-microRNA (miRNA) stem-loop overexpression only boosts guiding strand (i.e. miR-192-5p) expression, we adopted an artificial AAV(DJ)-directed, RNA Pol III promoter-driven miRNA hairpin construct for star-strand-specific overexpression in the liver. Liver steatosis and insulin resistance markers were evaluated in primary hepatocytes, mice with diabetes, and mice with excessive carbohydrate consumption.

Results

Functional loss of miR-192-3p in liver exacerbated hepatic micro-vesicular steatosis and insulin resistance in either mice with diabetes or wild-type mice with excessive fructose consumption. Liver-specific overexpression of miR-192-3p effectively halted hepatic steatosis and ameliorated insulin resistance in these mice models. Likewise, hepatocytes overexpressing miR-192-3p exhibited improved lipid accumulation, accompanied with decreases in lipogenesis and lipid-accumulation-related transcripts. Mechanistically, glucocorticoid receptor (GCR, also known as nuclear receptor subfamily 3, group C, member 1 [NR3C1]) was demonstrated to be negatively regulated by miR-192-3p. The effect of miR-192-3p on mitigating micro-vesicular steatosis was ablated by the reactivation of NR3C1.

Conclusions

The star strand miR-192-3p was an undermined glycerolipid regulator involved in controlling fat accumulation and insulin sensitivity in liver through blockade of hepatic GCR signalling; this miRNA may serve as a potential therapeutic option for the common co-mobility of diabetic mellitus and fatty liver disease.

Lay summary

The potential regulatory activity of star strand microRNA (miRNA) species has been substantially underestimated. In this study, we investigate the role and mechanism of an overlooked star strand miRNA (miR-192-3p) in regulating hepatic steatosis and insulin signalling in the livers of mice with diabetes and mice under excessive carbohydrate consumption.

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Liver-specific knockdown of miR-192-3p recapitulated functional loss of the miRNA as in mice with diabetes.

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This knockdown was characterised by pronounced hepatic micro-vesicular steatosis coupled to insulin resistance.

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In vivo overexpression of miR-192-3p alleviated hepatic steatosis in mice with diabetes and wild-type mice with excessive fructose consumption.

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Glucocorticoid receptor (also known as NR3C1) was discovered as the immediate target of miR-192-3p in regulating hepatic lipid turnover and storage.

Epicardial fat thickness can predict severity and multivessel distribution in Egyptian patients with atherosclerotic coronary artery stenosis

Background

Epicardial fat, in addition to its secretory function, may have an important role in predicting and stratifying cardiovascular risk. There is a paucity of data regarding correlation between epicardial fat thickness and coronary artery disease in Egypt.

Aim of the study

To study the relationship between epicardial fat thickness (EFT) measured by trans-thoracic echocardiography (TTE) and severity of coronary artery disease (CAD) and its distribution in Egyptian population.

Methods

Our study was a prospective observational case control study that was conducted upon 150 patients with stable CAD presented to the cardiology departments in Ain Shams University hospitals and Al-Zaitoun Specialized hospital from March to October, 2015. EFT was measured by TTE for all patients at the same day of performing invasive coronary angiography (CA). We studied the statistical correlation between EFT and presence of CAD, also we tried to find if EFT is related to severity of CAD (according to Gensini score) or its distribution.

Results

The study population was divided according to CA results to 2 groups; patients’ group having atherosclerotic CAD consisting of 100 patients and control group consisting of 50 patients with normal coronaries. All the well- known risk factors of CAD (male sex, smoking, hypertension, diabetes, dyslipidemia, increased body mass index) were significantly more prevalent in the patients’ group. Patients had significantly lower systolic and diastolic functions. EFT was significantly correlated to presence of CAD (P < 0.001) with a cut-off value of 5.5 mm. EFT was significantly correlated to severity of CAD assessed by Gensini score (P < 0.001). Also we found a significant positive correlation between EFT and number of vessels affected (P <  0.001).

Conclusion

EFT is a good predictor of CAD severity and multivessel affection in Egyptian patients. It is also a potentially promising predictor for the presence of CAD.

Body mass index is associated with region-dependent metabolic reprogramming of adipose tissue

Adipose tissue (AT) is involved in dysmetabolism pathogenesis. Regional fat distribution and functioning may contribute to obesity-related metabolic disorders and adverse health outcomes. Specific fat depots are suggested to possess unique biological properties, but specific metabolic profiles of subcutaneous (SAT) and visceral adipose tissue (VAT) remain unknown. We aimed to characterize VAT and SAT glucose metabolism, and their correlation with body mass index (BMI). AT samples from patients (n = 12; F:M, 9:3) with a mean age of 46 years (26–83 years) and an average BMI of 29.6 kg/m² (18–37 kg/m²) were used. VAT and SAT explants were obtained during elective laparoscopy, either cholecystectomy for uncomplicated cholelithiasis or gastric bypass for severe obesity. Explants were placed in insulin-free cell culture media and their metabolic profile was established by proton nuclear magnetic resonance. AT explants display a glucose and pyruvate consumption and acetate production that is region-dependent according to the patients BMI. In VAT, glucose consumption was positively correlated with BMI, while alanine and lactate production were negatively correlated with BMI, whereas in SAT the patients BMI did not affect AT secretome suggesting that increased BMI promotes a metabolic reprogramming of VAT towards de novo lipogenesis. This region-dependent metabolic reprogramming of AT associated with BMI was autonomous of insulin. This data, although preliminary, suggests that there is a BMI-related remodeling of glucose metabolism in VAT. Targeting this BMI-induced metabolic shift may represent a potential target to counteract unwanted consequences derived from visceral adiposity.

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Metabolic profile of adipose tissue (AT) explants was studied after culture in insulin-free media.

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Visceral adipose tissue (VAT) glucose consumption was positively correlated with patient's BMI.

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Alanine and lactate production by VAT were negatively correlated with patient's BMI.

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Patient's BMI did not affect subcutaneous adipose tissue (SAT) secretome.

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BMI-related metabolic remodeling in VAT occurs beyond insulin action.

Associations between plasma branched-chain amino acids, β-aminoisobutyric acid and body composition

Plasma branched-chain amino acids (BCAA) are elevated in obesity and associated with increased cardiometabolic risk. β-Aminoisobutyric acid (B-AIBA), a recently identified small molecule metabolite, is associated with decreased cardiometabolic risk. Therefore, we investigated the association of BCAA and B-AIBA with each other and with detailed body composition parameters, including abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). A cross-sectional study was carried out with lean (n 15) and obese (n 33) men and women. Detailed metabolic evaluations, including measures of body composition, insulin sensitivity and plasma metabolomics were completed. Plasma BCAA were higher (1·6 (se 0·08) (×10⁷) v. 1·3 (se 0·06) (×10⁷) arbitrary units; P = 0·005) in obese v. lean subjects. BCAA were positively associated with VAT (R 0·49; P = 0·0006) and trended to an association with SAT (R 0·29; P = 0·052). The association between BCAA and VAT, but not SAT, remained significant after controlling for age, sex and race on multivariate modelling (P < 0·05). BCAA were also associated with parameters of insulin sensitivity (Matsuda index: R −0·50, P = 0·0004; glucose AUC: R 0·53, P < 0·001). BCAA were not associated with B-AIBA (R −0·04; P = 0·79). B-AIBA was negatively associated with SAT (R −0·37; P = 0·01) but only trended to an association with VAT (R 0·27; P = 0·07). However, neither relationship remained significant after multivariate modelling (P > 0·05). Plasma B-AIBA was associated with parameters of insulin sensitivity (Matsuda index R 0·36, P = 0·01; glucose AUC: R −0·30, P = 0·04). Plasma BCAA levels were positively correlated with VAT and markers of insulin resistance. The results suggest a possible complex role of adipose tissue in BCAA homeostasis and insulin resistance.

Influences of nutrition and adiposity on bone mineral density in individuals with chronic spinal cord injury: A cross-sectional, observational study

BACKGROUND

Dietary inadequacy and adiposity, both prevalent in the chronic spinal cord injury (SCI) population, are known to influence bone turnover and may be potential modifiable risk factors for the development of sublesional osteoporosis following SCI. This pilot study in an SCI cohort aimed to assess measures of nutrition and obesity, to determine if these measures were associated with bone mineral density (BMD), and to compare these measures to a non-SCI control cohort.

METHODS

In a cross-sectional observational study, volunteers with chronic SCI (> 1 year post-injury, lesions from C1 to T12 and severity category A-D by the American Spinal Injury Association Impairment Scale) were assessed, and 8 non-SCI individuals were recruited as a comparison group. BMD at the femoral neck (FN) and lumbar spine (LS), and an estimate of visceral adipose tissue (VAT) from lumbar vertebrae 1 through 4 were measured using dual energy X-ray absorptiometry (DXA); nutrient intake of calcium, vitamins D & K, and protein were estimated using a food frequency questionnaire; plasma 25-hydroxyvitamin D (25(OH)D) was analyzed using ultra-high performance liquid chromatography/tandem mass spectroscopy; and serum leptin, adiponectin and insulin were analyzed using a multiplex assay.

RESULTS

A total of 34 individuals with SCI (n = 22 tetraplegic; n = 12 paraplegic; 94% male) who averaged 12.7 (9.0) years post-injury, age 40.0 (10.9) years and % body fat of 28.4 (7.3) were assessed. Multiple linear regression analyses in the SCI cohort showed significant associations between BMD at the FN and LS with leptin (FN: r = 0.529, p = 0.005; LS: r = 0.392, p = 0.05), insulin (FN: r = 0.544, p = 0.003; LS: r = 0.388, p = 0.05), and VAT percent (FN: r = 0.444, p = 0.02; LS: r = 0.381, p = 0.05). Adiponectin was only correlated with LS BMD (r = 0.429, p = 0.03). No significant relationships were found between BMD and serum 25(OH)D, or intakes of calcium, vitamins D & K, and protein. Intake of vitamin D was adequate in 69% of participants with SCI, where 91% of those persons consumed either vitamin D and/or multivitamin supplements. Vitamin D status was similar between SCI and non-SCI groups as was sub-optimal status (25(OH)D < 75 nmol/L) (60% of SCI compared to 50% of non-SCI). Participants with SCI had significantly lower FN BMD in comparison to non-SCI controls (p = 0.001).

CONCLUSIONS

Compromised BMD among individuals with SCI was not associated with a deficiency of vitamin D or other bone nutrients. The observed positive associations between BMD and leptin, insulin, adiponectin and VAT provide a framework to evaluate links between adiposity and bone health in a larger SCI cohort.

Regulatory role of CD40 in obesity-induced insulin resistance

Excessive nutrient intake in obesity triggers the accumulation of various types of immune cells in adipose tissue, particularly visceral adipose tissue (VAT). This can result in chronic inflammation which disrupts insulin effects on adipocytes and muscle cells and culminates in development of insulin resistance. The interplay between immune cells and adipose tissue is a key event for the development of insulin resistance that precedes type 2 diabetes. CD40, a well-documented costimulatory receptor, is required for efficient systemic adaptive immune responses. However, we and other groups recently showed that CD40 unexpectedly ameliorates inflammation in VAT and accordingly attenuates obesity-induced insulin resistance. Specifically, although CD40 is typically considered to play its principal immune roles on B lymphocytes and myeloid cells, we found that CD40(+)CD8(+) T lymphocytes were major contributors to the protective effect. This unexpected inhibitory role of CD40 on CD8(+) T cell activation in VAT may reflect unique features of this microenvironment. Additional knowledge gaps include whether CD40 also plays roles in mucosal immunity that control the homeostasis of gut microbiota, and human metabolic diseases. Potential therapeutic approaches, including stimulating CD40 signaling and/or manipulating specific CD40 signaling pathways in the VAT microenvironment, may open new avenues for treatment of obesity-induced insulin resistance, and prevention of type 2 diabetes.

Connecting metabolism to intestinal barrier function: The role of leptin

Structure and function of the intestinal epithelial barrier (IEB) are dependent upon the integrity of junctional protein structures sealing the apical surface between epithelial cells. Tight junctions (TJ) and the surrounding apical F-actin cytoskeleton are involved in the regulation of paracellular permeability. The regulation of actin cytoskeleton organization by RhoA/Rho-kinase (ROCK) pathway plays an important role in TJ assembly and function. There is mounting evidence that the adipocyte-derived hormone leptin exerts pleiotropic effects on the intestinal epithelium including nutrient absorption, epithelial growth, inflammation and injury. Leptin activates multiple cell signaling pathways in intestinal epithelial cells (IEC) that can explain these pleiotropic effects. However, these pathways are also involved in the primary role of leptin that is the regulation of energy and glucose metabolism homeostasis. In this commentary, we examine how the interplay between leptin signaling pathways that regulate cell metabolism could impact upon IEB function.

Methyl-donor supplementation in obese mice prevents the progression of NAFLD, activates AMPK and decreases acyl-carnitine levels

Non-alcoholic fatty liver disease (NAFLD) results from increased hepatic lipid accumulation and steatosis, and is closely linked to liver one-carbon (C1) metabolism. We assessed in C57BL6/N mice whether NAFLD induced by a high-fat (HF) diet over 8 weeks can be reversed by additional 4 weeks of a dietary methyl-donor supplementation (MDS). MDS in the obese mice failed to reverse NAFLD, but prevented the progression of hepatic steatosis associated with major changes in key hepatic C1-metabolites, e.g. S-adenosyl-methionine and S-adenosyl-homocysteine. Increased phosphorylation of AMPK-α together with enhanced β-HAD activity suggested an increased flux through fatty acid oxidation pathways. This was supported by concomitantly decreased hepatic free fatty acid and acyl-carnitines levels. Although HF diet changed the hepatic phospholipid pattern, MDS did not. Our findings suggest that dietary methyl-donors activate AMPK, a key enzyme in fatty acid β-oxidation control, that mediates increased fatty acid utilization and thereby prevents further hepatic lipid accumulation.