Weight loss allows the dissection of the interaction between abdominal fat and PNPLA3 (adiponutrin) in the liver damage of obese children

Nephrological, Pulmonary, and Dermatological Complications in the Context of MAFLD/NAFLD: A Narrative Review

Background: The most common cause of chronic liver disease is now known to be non-alcoholic fatty liver disease (NAFLD), recently redefined as metabolic-associated fatty liver disease (MAFLD). This review aims to synthesize current evidence on the pathophysiology and clinical implications of nephrological, pulmonary, and dermatological manifestations among NAFLD/MAFLD patients. In order to find safe and efficient treatments, NAFLD/MAFLD has emerged as a primary concern for hepatologists worldwide. Methods: We conducted a comprehensive review of the literature from major databases, focusing on studies that evaluated the extrahepatic manifestations of NAFLD/MAFLD. Emphasis was placed on identifying pathophysiological mechanisms and assessing their clinical impact on renal, pulmonary, and dermatological systems. Results: Recent developments in the management of chronic viral hepatitis have lowered the mortality rate associated with chronic liver disease. However, the prevalence of NAFLD/MAFLD continues to rise, making chronic liver disease a significant health concern for the future. An increasing percentage of patients on liver transplant waiting lists now have cirrhosis and hepatocellular carcinoma due to non-alcoholic liver disease. Furthermore, the incidence and prevalence of chronic kidney disease have surged, linking NAFLD/MAFLD to higher morbidity, mortality, and healthcare costs. Conclusions: NAFLD/MAFLD is underdiagnosed and underappreciated, yet its incidence is rapidly increasing, raising concerns about a potential global epidemic. Given its multisystemic impact-extending to renal, pulmonary, and dermatological complications-it is crucial to develop interdisciplinary strategies for early detection and effective management of the disease.

Genetic Markers Predisposing to Nonalcoholic Steatohepatitis

The growing prevalence of nonalcoholic fatty liver disease (NAFLD) has sparked interest in understanding genetics and epigenetics associated with the development and progression of the disease. A better understanding of the genetic factors related to progression will be beneficial in the risk stratification of patients. These genetic markers can also serve as potential therapeutic targets in the future. In this review, we focus on the genetic markers associated with the progression and severity of NAFLD.

PNPLA3 I148M and response to treatment for hepatic steatosis: A systematic review

BACKGROUND

It is unclear whether the patatin-like phospholipase domain-containing protein 3 (PNPLA3) rs738409 C-to-G single nucleotide polymorphism, resulting in the substitution of isoleucine to methionine at position 148 (I148M), impedes regression of hepatic steatosis when treating non-alcoholic fatty liver disease (NAFLD).

OBJECTIVES

Investigate if carriage of the PNPLA3 148M allele affects the anti-steatotic efficacy of all possible anti-NAFLD interventions, identify gaps in current knowledge and provide guidance for individual treatment.

METHODS

Research available in public databases was searched up to 13 November 2022. Studies were included if a treatment in NAFLD patients decreased hepatic steatosis in the pooled patient group or a PNPLA3 I148M polymorphism subgroup (II/IM/MM). The risk of bias was assessed using the Cochrane Risk-Of-Bias 2 Tool and the Newcastle-Ottawa Scale.

RESULTS

Moderate evidence indicates that NAFLD patients homozygous for the PNPLA3 148M allele benefit less or not at all from omega-3 carboxylic acids to decrease liver fat, while the PNPLA3 148I allele shows moderate benefit. Low evidence suggests that interventions employing lifestyle changes are more effective to reduce liver fat in NAFLD patients homozygous for the PNPLA3 148M allele compared to patients with wild-type PNPLA3.

CONCLUSIONS

NAFLD patients homozygous for the PNPLA3 148M allele might not benefit from omega-3 carboxylic acids to reduce hepatic steatosis in contrast to patients with wild-type PNPLA3. Instead, patients with two PNPLA3 148M alleles should be especially advised to adopt lifestyle changes. Genotyping for PNPLA3 I148M should be encouraged in therapeutic studies for NAFLD.

REGISTRATION NUMBER (PROSPERO)

CRD42022375028.

Clinical features and metabolic complications for non-alcoholic fatty liver disease (NAFLD) in youth with obesity

Pediatric obesity has become in the last forty years the most common metabolic disease in children and adolescents affecting about 25% of the pediatric population in the western world. As obesity worsens, a whole-body insulin resistance (IR) occurs. This phenomenon is more pronounced during adolescence, when youth experience a high degree of insulin resistance due the production of growth hormone. As IR progresses, the blunted control of insulin on adipose tissue lipolysis causes an increased flux of fatty acids with FFA deposition in ectopic tissues and organs such as the liver, leading to the development of NAFLD. In this brief review, we will discuss the clinical implications of IR and NAFLD in the context of pediatric obesity. We will review the pathogenesis and the link between these two entities, the major pathophysiologic underpinnings, including the role of genetics and metagenomics, how these two entities lead to the development of type 2 diabetes, and which are the therapeutic options for NAFLD in youth.

Advances in pediatric non-alcoholic fatty liver disease: From genetics to lipidomics

As a result of the obesity epidemic, non-alcoholic fatty liver disease (NAFLD) represents a global medical concern in childhood with a closely related increased cardiometabolic risk. Knowledge on NAFLD pathophysiology has been largely expanded over the last decades. Besides the well-known key NAFLD genes (including the I148M variant of the PNPLA3 gene, the E167K allele of the TM6SF2, the GCKR gene, the MBOAT7-TMC4 rs641738 variant, and the rs72613567:TA variant in the HSD17B13 gene), an intriguing pathogenic role has also been demonstrated for the gut microbiota. More interestingly, evidence has added new factors involved in the "multiple hits" theory. In particular, omics determinants have been highlighted as potential innovative markers for NAFLD diagnosis and treatment. In fact, different branches of omics including metabolomics, lipidomics (in particular sphingolipids and ceramides), transcriptomics (including micro RNAs), epigenomics (such as DNA methylation), proteomics, and glycomics represent the most attractive pathogenic elements in NAFLD development, by providing insightful perspectives in this field. In this perspective, we aimed to provide a comprehensive overview of NAFLD pathophysiology in children, from the oldest pathogenic elements (including genetics) to the newest intriguing perspectives (such as omics branches).

Association between Hepatic Steatosis and Obstructive Sleep Apnea in Children and Adolescents with Obesity

BACKGROUND

Owing to the increasing rate of pediatric obesity, its complications such as non-alcoholic fatty liver disease (NAFLD) and obstructive sleep apnea (OSA) have become prevalent already in childhood. We aimed to assess the relationship between these two diseases in a cohort of children with obesity.

METHODS

We enrolled 153 children with obesity (mean age 10.5 ± 2.66, mean BMI 30.9 ± 5.1) showing OSA. Subjects underwent a laboratory evaluation, a cardio-respiratory polysomnography (PSG), and a liver ultrasound.

RESULTS

All subjects had a clinical diagnosis of OSA based on the AHI > 1/h (mean AHI 8.0 ± 5.9; range 2.21-19.0). Of these, 69 showed hepatic steatosis (62.3% as mild, 20.3% as moderate, and 17.4% as severe degree). A strong association between ALT and apnea/hypopnea index (AHI) was observed (p = 0.0003). This association was not confirmed after adjusting for hepatic steatosis (p = 0.53). By subdividing our population according to the presence/absence of steatosis, this association was found only in the steatosis group (p = 0.009). As the severity of steatosis increased, the significance of its association with AHI compared to the absence of steatosis became progressively stronger (all p < 0.0001).

CONCLUSIONS

Hepatic steatosis seems to drive the association between OSA and ALT levels, suggesting a potential pathogenic role of OSA in NAFLD.

Non-Alcoholic Fatty Liver Disease in Lean and Non-Obese Individuals: Current and Future Challenges

Non-alcoholic fatty liver disease (NAFLD), which approximately affects a quarter of the world’s population, has become a major public health concern. Although usually associated with excess body weight, it may also affect normal-weight individuals, a condition termed as lean/non-obese NAFLD. The prevalence of lean/non-obese NAFLD is around 20% within the NAFLD population, and 5% within the general population. Recent data suggest that individuals with lean NAFLD, despite the absence of obesity, exhibit similar cardiovascular- and cancer-related mortality compared to obese NAFLD individuals and increased all-cause mortality risk. Lean and obese NAFLD individuals share several metabolic abnormalities, but present dissimilarities in genetic predisposition, body composition, gut microbiota, and susceptibility to environmental factors. Current treatment of lean NAFLD is aimed at improving overall fitness and decreasing visceral adiposity, with weight loss strategies being the cornerstone of treatment. Moreover, several drugs including PPAR agonists, SGLT2 inhibitors, or GLP-1 receptor agonists could also be useful in the management of lean NAFLD. Although there has been an increase in research regarding lean NAFLD, there are still more questions than answers. There are several potential drugs for NAFLD therapy, but clinical trials are needed to evaluate their efficacy in lean individuals.

A review of non-alcoholic fatty liver disease in non-obese and lean individuals

Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of hepatic disorders. It represents a wide range of chronic liver diseases in patients with no history of significant alcohol consumption, starting with simple steatosis and progressing towards non-alcoholic steatohepatitis, cirrhosis, and ultimately hepatocellular carcinoma. NAFLD is usually associated with type 2 diabetes mellitus, dyslipidemia, metabolic syndrome, and obesity. This disease has mostly been studied in obese individuals; however, it has been widely reported and studied among the lean/non-obese population in recent years. The pathogenesis of NAFLD in non-obese patients is associated with various genetic predispositions, particularly a patatin-like phospholipase domain-containing protein 3 G allele polymorphism, which results in the accumulation of triglyceride in the liver and resistance to insulin. Additionally, dietary factors such as high fructose consumption seem to play a substantial role in the pathology of non-obese NAFLD. Although there is not enough evidence on the treatment of NAFLD in non-obese patients, the standard approach is to advise altering one's lifestyle in order to diminish visceral adiposity. Dietary modification, weight loss, and increased physical activity are highly recommended. We aimed to review and summarize the existing information on the prevalence, pathogenesis, genetic predispositions, diagnosis, and treatment of NAFLD in non-obese patients according to the latest literature.

Aceclofenac-induced hepatotoxicity: An ameliorative effect of Terminalia bellirica fruit and ellagic acid

BACKGROUND

Aceclofenac (ACF), a widely used nonsteroidal anti-inflammatory drug, has been associated with a number of severe cases of clinical hepatotoxicity. Terminalia bellirica, an evergreen tree, is known to have several ethnomedicinal uses including antioxidant and hepatoprotective effects. Hence T. bellirica fruit extracts and its phytoconstituent ellagic acid (EA) are expected to provide protection against oxidative stress and liver damage produced by long-term use of ACF.

AIM

To evaluate the antioxidant and hepatoprotective activities of T. bellirica fruit extracts and EA against ACF-induced toxicity in albino Wistar rats.

METHODS

The in vitro antioxidant activities of T. bellirica fruit ethyl acetate and aqueous extracts were measured by metal ion chelation and nitric oxide radical scavenging assays. The in vivo antioxidant and hepatoprotective effects of T. bellirica extracts (200 mg/kg) and EA (40 mg/kg) in ACF-induced hepatotoxic rats were assessed in serum and liver tissue after oral administration for 21 d. Silymarin (40 mg/kg) was used as a standard control. Oxidative stress markers in the blood (ferric reducing ability of plasma and lipid peroxidation inhibition) and liver tissues (superoxide dismutase, catalase and malondialdehyde) were analyzed using standard protocols. Liver function markers such as alkaline phosphatase, glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, lactate dehydrogenase, γ-glutamyl transferase, creatinine, total protein, and uric acid were evaluated in rat serum.

RESULTS

The T. bellirica fruit ethyl acetate extract exhibited superior metal ion chelating and nitric oxide radical scavenging abilities during in vitro antioxidant assays as compared to aqueous extracts. Oral administration of ACF in rats (15 mg/kg) for 21 d produced oxidative stress and adversely affected liver function suggesting liver injury. Treatment with extracts (ethyl acetate and aqueous), EA and silymarin accounted for a significant reduction in the adverse effects of ACF on oxidative stress and liver function markers in serum and hepatic tissue in rats. Histopathological evaluation of the liver indicated that the extracts and EA significantly decreased the degree of liver damage. The in vivo efficacy of EA was higher than T. bellirica fruit extracts. Of these extracts, ethyl acetate extract revealed comparatively better antioxidant and hepatoprotective activity.

CONCLUSION

Ellagic acid and T. bellirica fruit extracts exhibited considerable hepatoprotective and antioxidant activities in long-term ACF-treated rats.

Nonalcoholic Fatty Liver Disease in Children: Unique Considerations and Challenges

Nonalcoholic fatty liver disease (NAFLD) is increasing in prevalence in concert with the global epidemic of obesity and is being diagnosed at increasingly younger ages. The unique histologic features and early presentation of disease in pediatrics suggest that children and adults may differ with regard to etiopathogenesis, with children displaying a greater vulnerability to genetic and environmental factors. Of significant relevance to pediatrics, in utero and perinatal stressors may alter the lifelong health trajectory of a child, increasing the risk of NAFLD and other cardiometabolic diseases. The development and progression of disease in childhood is likely to carry increased risk of long-term morbidity. Novel biomarkers and therapeutic agents are needed to avoid the otherwise inevitable health and societal consequences of this rapidly expanding pediatric population.

Toward Genetic Prediction of Nonalcoholic Fatty Liver Disease Trajectories: PNPLA3 and Beyond

Nonalcoholic fatty liver disease (NAFLD) is on the verge of becoming the leading cause of liver disease. NAFLD develops at the interface between environmental factors and inherited predisposition. Genome-wide association studies, followed by exome-wide analyses, led to identification of genetic risk variants (eg, PNPLA3, TM6SF2, and SERPINA1) and key pathways involved in fatty liver disease pathobiology. Functional studies improved our understanding of these genetic factors and the molecular mechanisms underlying the trajectories from fat accumulation to fibrosis, cirrhosis, and cancer over time. Here, we summarize key NAFLD risk genes and illustrate their interactions in a 3-dimensional "risk space." Although NAFLD genomics sometimes appears to be "lost in translation," we envision clinical utility in trial design, outcome prediction, and NAFLD surveillance.

Nutrition and Genetics in NAFLD: The Perfect Binomium

Nonalcoholic fatty liver disease (NAFLD) represents a global healthcare burden since it is epidemiologically related to obesity, type 2 diabetes (T2D) and Metabolic Syndrome (MetS). It embraces a wide spectrum of hepatic injuries, which include simple steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis and hepatocellular carcinoma (HCC). The susceptibility to develop NAFLD is highly variable and it is influenced by several cues including environmental (i.e., dietary habits and physical activity) and inherited (i.e., genetic/epigenetic) risk factors. Nonetheless, even intestinal microbiota and its by-products play a crucial role in NAFLD pathophysiology. The interaction of dietary exposure with the genome is referred to as 'nutritional genomics,' which encompasses both 'nutrigenetics' and 'nutriepigenomics.' It is focused on revealing the biological mechanisms that entail both the acute and persistent genome-nutrient interactions that influence health and it may represent a promising field of study to improve both clinical and health nutrition practices. Thus, the premise of this review is to discuss the relevance of personalized nutritional advices as a novel therapeutic approach in NAFLD tailored management.

Extrahepatic Manifestations of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and encompasses a spectrum of pathology from simple steatosis to inflammation and significant fibrosis that leads to cirrhosis. NAFLD and its comorbid conditions extend well beyond the liver. It is a multisystemic clinical disease entity with extrahepatic manifestations such as cardiovascular disease, type 2 diabetes, chronic kidney disease, hypothyroidism, polycystic ovarian syndrome, and psoriasis. Indeed, the most common causes of mortality in subjects with NAFLD are cardiovascular disease, followed by malignancies and then liver-related complications as a distant third. This review focuses on several of the key extrahepatic manifestations of NAFLD and areas for future investigation. Clinicians should learn to screen and initiate treatment for these extrahepatic manifestations in a prompt and timely fashion before they progress to end-organ damage.

A Pilot Study Assessing the Possible Combined Effect of Physical Activity and PNPLA3 rs738409 Polymorphism on the Risk for Non-Alcoholic Fatty Liver Disease in the Japanese Elderly General Population

PURPOSE

The patatin-like phospholipase domain containing protein 3 (PNPLA3) rs738409 polymorphism (c.444C>G) is the most well-known genetic risk factor for non-alcoholic fatty liver disease (NAFLD), but whether or not physical activity influences the association between the PNPLA3 genotype and risk of NAFLD is unclear.

PATIENTS AND METHODS

A retrospective longitudinal analysis was conducted among 352 Japanese subjects. Each type of physical activity was assigned a metabolic equivalent (MET), and the subjects were classified into sedentary, low or high groups using the "METS*T" (METs × hours per week) value of 5 or 21 as a threshold.

RESULTS

Among the PNPLA3 G/G genotype carriers, the high and low METS*T groups had a lower risk of NAFLD than the sedentary METS*T group (odds ratio [95% confidence interval]: 0.14 [0.02-0.99] and 0.16 [0.03-1.04], respectively). Furthermore, the PNPLA3 C/C or C/G genotype carriers showed no significant difference in the risk of NAFLD among the three METS*T groups.

CONCLUSION

The PNPLA3 rs738409 genotype may be associated with the beneficial effects of physical activity on the risk of NAFLD among elderly Japanese individuals. Further comprehensive investigations are therefore needed to verify the preliminary results.

Short-term Dietary Interventions for the Management of Nonalcoholic Fatty Liver

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) affects millions of individuals on a global scale and currently no gold standard treatment exists. The risk of developing NAFLD is considerably higher with increasing body mass index. Consequently, weight loss should be recommended to all overweight patients with fatty liver. However, lifestyle interventions, irrespective of weight status, may also influence the condition. The aim herein is to present examples of short-term interventions which assess direct effects of dietary-related components on hepatic steatosis.

METHODS

This review includes studies with short-term dietary-related interventions of up to 16 weeks that evaluate their efficacy in reducing intrahepatic lipid contents (hepatic steatosis). This review primarily focuses on the three main macronutrients: dietary carbohydrates, fats and proteins.

RESULTS

High saturated fat intake and high consumption of carbohydrates, particularly from simple sugars such as fructose are reported as risk factors for hepatic steatosis. Overall, shortterm hypocaloric diets have shown beneficial effects in reducing intrahepatic lipid contents. Macronutrient manipulations such as carbohydrate restriction as well as the consumption of unsaturated fatty acids are also reported to have efficacious effects.

CONCLUSION

This review highlights the different dietary interventions that can influence hepatic steatosis in the short term, illustrating both pro and anti-steatotic effects.

Nonalcoholic fatty liver disease and eGFR levels could be linked by the PNPLA3 I148M polymorphism in children with obesity

BACKGROUND

PNPLA3 I148M polymorphism has an effect on modulation of estimated glomerular filtration rate (eGFR) in nonobese nondiabetic adults and in children with histologically confirmed nonalcoholic fatty liver disease (NAFLD).

OBJECTIVES

The objective of the study is to explore the impact of PNPLA3 I148M polymorphism on eGFR in children with obesity with and without NAFLD.

METHODS

We genotyped 591 patients with obesity for PNPLA3 I148M polymorphism. Anthropometrical, biochemical, and instrumental data were collected. NAFLD was defined by the presence of ultrasound-detected liver steatosis and/or ALT levels greater than 40 IU/L.

RESULTS

Patients with NAFLD showed significantly lower eGFR levels compared with subjects without NAFLD. Children with PNPLA3 MM genotype showed lower eGFR levels compared with those with either PNPLA3 IM or II genotypes both in the presence and absence of NAFLD. A general linear model for eGFR variance, including gender, duration of obesity, PNPLA3 genotypes, HOMA, BMI-SDS, LDL-C, and triglycerides as covariates, confirmed an inverse association between eGFR and PNPLA3 genotype only in the presence of NAFLD.

CONCLUSIONS

Children with obesity and PNPLA3 MM genotype show lower eGFR levels compared with other genotypes, with a major effect of this polymorphism in the presence of NAFLD.

Clinical and pathological features of sarcopenia-related indices in patients with non-alcoholic fatty liver disease

BACKGROUND

Sarcopenia is diagnosed with the skeletal muscle index (SMI) or the sarcopenia index (SI). We previously reported that the ratio of skeletal muscle mass to body fat mass (SF ratio) was a novel index of sarcopenia in patients with non-alcoholic fatty liver disease (NAFLD). The aim of this retrospective study was to evaluate sarcopenia with these indices in patients with NAFLD.

METHODS

One hundred and fifty-six consecutive patients with biopsy-proven NAFLD and alanine aminotransferase (ALT) >40 IU/L were enrolled. Liver function and body composition were evaluated in 121 patients after 12 months. We evaluated the relationship between histological findings, changes in liver function, and the SMI, SI, and SF ratio.

RESULTS

Of the 156 patients enrolled, 13.5% and 26.3% were diagnosed with sarcopenia with the SMI and SI. In patients with hepatic fibrosis stage <2, the SI and the SF ratio were significantly greater than in patients with fibrosis stage ≥2. There was no difference in SMI between groups. In the cohort assessed at baseline and 12 months later, transaminase activity and SMI decreased significantly, and the SF ratio increased over time. A multivariate analysis revealed the presence of the PNPLA3 G allele and an increase in SF ratio (odds ratio, 7.406) as predictive factors of ALT reduction >30% from baseline.

CONCLUSIONS

Due to the high prevalence of obesity, we should consider both skeletal muscle mass and body fat mass in the diagnosis and treatment of NAFLD. The SF ratio could be a useful index in sarcopenic NAFLD.

Pathogenesis of non-alcoholic fatty liver disease in children and adolescence: From “two hit theory” to “multiple hit model”

Nonalcoholic fatty liver disease (NAFLD) has become the dominant form of chronic liver disease in children and adolescents with the increasing prevalence of obesity worldwide. NAFLD represents a wide spectrum of conditions, ranging from fatty liver - which generally follows a benign, non-progressive clinical course - to non-alcoholic steatohepatitis, a subset of NAFLD that may progress to cirrhosis and end-stage liver disease or liver carcinoma. The underlying pathophysiological mechanism of “pediatric” NAFLD remains unclear, although it is strongly associated with obesity and insulin resistance. In this review we provide a general overview on the current understanding of NAFLD in children and adolescents, which underpins practice, enabling early diagnosis and appropriate therapeutic intervention for this life-threatening liver disease.

The Membrane-bound O-Acyltransferase7 rs641738 Variant in Pediatric Nonalcoholic Fatty Liver Disease

BACKGROUND

The rs641738 polymorphism in the membrane-bound O-acyltransferase domain containing protein 7 (MBOAT7) gene has been associated with increased risk of nonalcoholic fatty liver disease (NAFLD).

OBJECTIVES

To investigate the association between the MBOAT7 rs641738 polymorphism and both hepatic steatosis and biochemical markers of liver damage and to evaluate the potential additive effect of this variant and the I148M patatin-like phospholipase domain-containing 3 (PNPLA3) and the rs58542926 transmembrane 6 superfamily member 2 (TM6SF2) polymorphisms.

METHODS

One thousand and 2 obese children were genotyped for MBOAT7, PNPLA3, and TM6SF2 polymorphisms and underwent anthropometrical, ultrasonographic, and biochemical evaluation. Indirect measurement of liver fibrosis (Pediatric NAFLD Fibrosis Index [PNFI]) and a genetic risk score from these polymorphisms were calculated.

RESULTS

Carriers of the MBOAT7 T allele showed both higher alanine transaminase (ALT) (P = 0.004) and PNFI values (P = 0.04) than noncarriers. These findings were confirmed also for the carriers of the MBOAT7 T allele polymorphism with hepatic steatosis compared with noncarriers. A higher genetic risk score was associated with higher ALT (P = 0.011) and with an odds ratio (OR) to show elevated ALT of 3.4 (95% CI 1.3-5.5, P = 0.003). Patients belonging to genetic risk score 3 group had an OR to present steatosis of 2.6 (95% CI 1.43-4.83, P = 0.0018) compared with those belonging to lower genetic risk score group.

CONCLUSIONS

We first demonstrated in childhood obesity the role of the MBOAT7 rs641738 variant on serum ALT and the combined effect of the MBOAT7, PNPLA3, and TM6SF2 variants on NAFLD risk. We also provided the first pediatric association of the MBOAT7 polymorphism with indirect markers of liver fibrosis.

Aqueous leaves extract of Madhuca longifolia attenuate diclofenac-induced hepatotoxicity: Impact on oxidative stress, inflammation, and cytokines

Diclofenac is a Non-Steroidal Anti-inflammatory drug which is used as an analgesic. It is known to cause heptotoxicity on over dose and long term usage. Madhuca longifolia is an evergreen tree found widely in India that is known to have several ethnomedical uses. The aim of our study is to evaluate the beneficial effect of the aqueous leaf extract of M. longifolia against diclofenac-induced toxicity. Rats were dived into five groups of six rats each. Group-I was normal control. Group-II was administered with diclofenac (50 mg/kg. b.w./day, i.p) on 4th and 5th day. Group-III rats were treated with aqueous leaf extract of M. longifolia (500 mg/kg b.w./day, oral) for 5 consecutive days and diclofenac (50 mg/kg. b.w./day, i.p) was given on 4th and 5th day. Silymarin (25 mg/kg. b.w./day, oral) was used as standard drug which was given to the rats of group-IV along with diclofenac on 4th and 5th day. Aqueous leaf extract of M. longifolia (500 mg/kg b.w./day, oral) alone was administered in group-V. After the study period, the rats were evaluated for liver enzyme markers, antioxidant parameters, histopathological changes, and cytokines levels. The hepatic proinflammatory mediator cytokines like TNF-α, IL-6, and IL-1β were evaluated through ELISA. The protein expression of Caspase-3, COX-2, and NF-κB were analysed through Western blotting techniques. Aqueous leaves extract of M. longifolia was able to normalize the changes caused by diclofenac. Current study indicatesthe protective effect of the aqueous leaves extract of M. longifolia against diclofenac-induced toxicity.

Genetics and epigenetics of NAFLD and NASH: Clinical impact

Non-alcoholic fatty liver disease (NAFLD) is now recognised as the most common liver disease worldwide. It encompasses a broad spectrum of conditions, from simple steatosis, through non-alcoholic steatohepatitis, to fibrosis and ultimately cirrhosis and hepatocellular carcinoma. A hallmark of NAFLD is the substantial inter-patient variation in disease progression. NAFLD is considered a complex disease trait such that interactions between the environment and a susceptible polygenic host background determine disease phenotype and influence progression. Recent years have witnessed multiple genome-wide association and large candidate gene studies, which have enriched our understanding of the genetic basis of NAFLD. Notably, the I148M PNPLA3 variant has been identified as the major common genetic determinant of NAFLD. Variants with moderate effect size in TM6SF2, MBOAT7 and GCKR have also been shown to have a significant contribution. The premise for this review is to discuss the status of research into important genetic and epigenetic modifiers of NAFLD progression. The potential to translate the accumulating wealth of genetic data into the design of novel therapeutics and the clinical implementation of diagnostic/prognostic biomarkers will be explored. Finally, personalised medicine and the opportunities for future research and challenges in the immediate post genetics era will be illustrated and discussed.

Novel association between the nonsynonymous A803G polymorphism of the N-acetyltransferase 2 gene and impaired glucose homeostasis in obese children and adolescents

BACKGROUND

The N-acetyltransferase 2 ( NAT2 ) A803G polymorphism has been associated with decreased insulin sensitivity in a large adult population with the A allele associated with insulin-resistance-related traits.

OBJECTIVE

Evaluate the association of this polymorphism with anthropometric and metabolic parameters in obese children and adolescents.

SUBJECTS

A total of 748 obese children and adolescents were enrolled.

METHODS

Anthropometric and laboratory data were collected. During oral glucose tolerance test, the presence of a possible exaggerated plasma glucose excursion at 1 h (1HPG) or impaired glucose tolerance (IGT) was considered. Homeostasis model assessment, oral disposition index (oDI) and insulinogenic index (IDI) were calculated. Patients were genotyped for the NAT2 A803G polymorphism.

RESULTS

The prevalence of both IGT and elevated-1HPG was higher in children carrying the A803 allele (P = .02 and P = .03). Moreover, this allele was associated with both oDI and IGI reduction (P = .01). No differences among the NAT2 A803G genotypes for the other parameters were shown. Children homozygous for the A allele presented an odds ratio (OR), to show IGT of 4.9 (P = .01). Children both homozygous and heterozygous for the A allele had higher risk to show elevated-1HPG (OR of 2.7, P = .005; and OR = 2.3, P = .005) compared with patients homozygous for the NAT2 803G allele.

CONCLUSIONS

NAT2 A803 allele seems to play a role in worsening the destiny of obese children carrying it, predisposing them to elevated-1HPG and IGT and then to a possible future type 2 diabetes mellitus throughout an impairment of pancreatic β-cellular insulin secretion as suggested by oDI and IGI reduction.

The Association between Pediatric NAFLD and Common Genetic Variants

Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of obesity. Several studies have shown that genetic predisposition probably plays an important role in its pathogenesis. In fact, in the last few years a large number of genetic studies have provided compelling evidence that some gene variants, especially those in genes encoding proteins regulating lipid metabolism, are associated with intra-hepatic fat accumulation. Here we provide a comprehensive review of the gene variants that have affected the natural history of the disease.

Nonobese Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) refers to a group of conditions characterized by hepatic steatosis in the absence of significant alcohol consumption. NAFLD is seen commonly in patients with metabolic abnormalities associated with obesity, such as type II diabetes, dyslipidemia, and metabolic syndrome. Evidently, however, not all obese subjects develop NAFLD and, more importantly, NAFLD can be found in nonobese individuals. Although NAFLD occurring in nonobese subjects has been reported in children and adults of all ethnicities, it appears to be recognized more frequently in Asians, even when strict ethnicity-specific body mass index criteria are used to define obesity. Studies based on liver biopsies suggest that the prevalence of nonalcoholic steatohepatitis and fibrosis does not differ significantly between nonobese NAFLD and NAFLD in obese patients. Visceral obesity as opposed to general obesity, high fructose and cholesterol intake, and genetic risk factors (eg, palatin-like phospholipase domain-containing 3) may be associated with nonobese NAFLD. In general, nonalcoholic steatohepatitis is associated with increased mortality, primarily from cardiovascular causes, independent of other metabolic factors. Although data regarding the mortality impact of nonobese NAFLD are not as mature, it may be important to identify high-risk nonobese NAFLD patients and manage their metabolic profile. Currently, lifestyle modification to reduce visceral adiposity, including dietary changes and physical activity, remains the standard of care in patients with nonobese NAFLD.

PNPLA3 p.I148M variant is associated with greater reduction of liver fat content after bariatric surgery

BACKGROUND

Obesity is the major trigger of nonalcoholic fatty liver disease (NAFLD). NAFLD is further favored by the patatin-like phospholipase domain-containing 3 (PNPLA3) p.I148M, transmembrane 6 superfamily member 2 (TM6SF2) p.E167K, and membrane-bound O-acyltransferase domain containing 7 (MBOAT7) rs641738 variants.

OBJECTIVES

To investigate the relationship between the PNPLA3, TM6SF2, and MBOAT7 genotypes and the outcomes of bariatric surgery.

SETTING

University hospital.

METHODS

Prospectively we monitored 84 obese individuals (body mass index 35-64 kg/m2) scheduled for bariatric surgery. The PNPLA3 p.I148M, TM6SF2 p.E167K, and MBOAT7 rs641738 variants were genotyped using restriction fragment length polymorphism analysis and TaqMan assays. Hepatic steatosis was determined before surgery using analysis of liver biopsy samples and a novel magnetic resonance imaging-based equation. One year later, steatosis was reevaluated by magnetic resonance imaging.

RESULTS

The presence of the PNPLA3 allle [M] was associated with increased hepatic triglyceride content (P = .03), steatosis detected by magnetic resonance imaging (P = 0.04), and decreased serum glucose concentrations (P = .04). Neither variant TM6SF2 nor MBOAT7 increased hepatic steatosis (all P>.05); however, the MBOAT7 polymorphism was associated with increased triglyceride, total cholesterol, low density lipoprotein, and serum glucose levels (all P<.05). Patients carrying the prosteatotic PNPLA3 allele [M] lost more weight (P<.01) and liver fat (P = .04) one year after surgery, as compared to individuals having the common genotype. The PNPLA3 genotype and initial grade of steatosis, but not the TM6SF2 or MBOAT7 variants, were independent predictors of NAFLD improvement (P = .03 and P<.01, respectively).

CONCLUSION

In obese patients, the presence of the PNPLA3 p.I148M allele might be associated with greater improvement of hepatic steatosis after bariatric surgery in comparison to carriers of PNPLA3 wild-type alleles.

TM6SF2 Glu167Lys polymorphism is associated with low levels of LDL-cholesterol and increased liver injury in obese children

BACKGROUND

The Glu167Lys (E167K) transmembrane 6 superfamily member 2 (TM6SF2) variant has been associated with liver steatosis, high alanine transaminase (ALT) levels and reduced plasma levels of liver-derived triglyceride-rich lipoproteins.

OBJECTIVES

The objectives of this study were to investigate in a group of obese children the association among the 167K allele of TM6SF2 gene and ALT, cholesterol and triglycerides levels, and hepatic steatosis, and to evaluate the potential interaction between this variant and the I148M patatin like phospholipase 3 gene (PNPLA3) polymorphism on liver enzymes.

METHODS

We genotyped 1010 obese children for TM6SF2 E167K and PNPLA3 I148M polymorphisms. Anthropometrical and biochemical data were collected. Ultrasound imaging of the liver was performed.

RESULTS

The 167K allele showed an association with steatosis (P < 0.0001), higher ALT levels (P < 0.001) and lower total cholesterol (P < 0.00001), low-density lipoprotein cholesterol (P < 0.0001), triglycerides (P = 0.02) and non-high-density lipoprotein cholesterol levels (P < 0.000001). The subjects homozygous for the PNPLA3 148M allele carrying the rare variant of TM6SF2 showed an odds ratio of 12.2 (confidence interval 3.8-39.6, P = 0.000001) to present hypertransaminasaemia compared with the remaining patients.

CONCLUSION

Although the TMS6SF2 E167K variant predisposes the obese children to non-alcoholic fatty liver disease, there is an association between this variant and lower levels of cardiovascular risk factors. Overall, the data suggest differential effects of TMS6SF2 E167K variant on liver and heart health.

Iron Metabolism Dysregulation and Cognitive Dysfunction in Pediatric Obesity: Is There a Connection?

Obesity and iron deficiency (ID) are two of the most common nutritional disorders in the world. In children both conditions deserve particular attention. Several studies revealed an association between obesity and iron deficiency in children and, in some cases, a reduced response to oral supplementation. The connecting mechanism, however, is not completely known. This review is focused on: (1) iron deficiency in obese children and the role of hepcidin in the connection between body fat and poor iron status; (2) iron status and consequences on health, in particular on cognitive function; (3) cognitive function and obesity; (4) suggestion of a possible link between cognitive dysfunction and ID in pediatric obesity; and implications for therapy and future research.

Patatin-like phospholipase 3 (rs738409) gene polymorphism is associated with increased liver enzymes in obese adolescents and metabolic syndrome in all ages

BACKGROUND

Obesity is associated with non-alcoholic fatty liver disease (NAFLD), and the patatin-like phospholipase 3 (PNPLA3) rs738409 (Ile148Met, C>G) gene polymorphism is one of the most important genetic determinants of NAFLD. Carriers have been reported to better respond to lifestyle modification.

AIM

To investigate the effect of rs738409 on overweight/obese adolescents and adults with and without metabolic syndrome (MetS).

METHODS

Two hundred and eighty-eight overweight/obese and 209 normal weight participants of the STYJOBS/EDECTA cohort (NCT00482924) were analysed for PNPLA3 genotypes.

RESULTS

Compared to overweight/obese without MetS, in overweight/obese study participants with MetS, the presence of the G allele (148Met) was significantly higher (CC: 5.0% vs. 9.2%, Spearman's correlation, 0.12; P = 0.038). Persons with CG (heterozygote for the risk allele) and with GG (homozygote for the risk allele) genotypes showed significantly higher ALT levels than those with CC genotypes. Even young individuals aged below 20 years had significantly increased ALT levels if they were homozygote with the G allele.

CONCLUSIONS

The PNPLA3 rs738409 polymorphism is associated already in youths with increased ALT, and is more frequent in obese with MetS of all ages. Hence, overweight/obese rs738409 carriers should be identified early in life and treated with a rigorous life style intervention.

PNPLA3 gene polymorphism and response to lifestyle modification in patients with nonalcoholic fatty liver disease

BACKGROUND AND AIM

Lifestyle modification is the cornerstone for the management of nonalcoholic fatty liver disease (NAFLD), and patatin-like phospholipase 3 (PNPLA3) is one of the most important genetic determinants of NAFLD. We aimed to investigate the effect of PNPLA3 gene polymorphism on the response to lifestyle modification in NAFLD patients.

METHODS

This was a post-hoc analysis of a randomized controlled trial on a lifestyle modification program in community NAFLD patients. The PNPLA3 rs738409 gene polymorphism was correlated with changes in metabolic profile and intrahepatic triglyceride content (IHTG) as measured by proton magnetic resonance spectroscopy.

RESULTS

One hundred and fifty-four patients were equally randomized into the intervention and control groups. The presence of G allele was associated with greater reduction in IHTG (CC: 3.7 ± 5.2%, CG: 6.5 ± 3.6%), and GG: 11.3 ± 8.8% (Spearman's correlation, 0.34; P = 0.002), body weight (P = 0.030), waist-to-hip ratio (P = 0.024), total cholesterol (P = 0.031), and low-density lipoprotein cholesterol (P = 0.009) in the intervention group. In contrast, PNPLA3 polymorphism had no impact on IHTG changes in the control group. By multivariable analysis, PNPLA3 genotype and body mass index (BMI) change were independently associated with IHTG reduction in the intervention group. Only BMI change was associated with IHTG reduction in the control group.

CONCLUSION

Although the PNPLA3 rs738409 GG genotype confers a higher risk of NAFLD, these patients are more sensitive to the beneficial effects of lifestyle modification and should be encouraged to do so.

Novel association between a nonsynonymous variant (R270H) of the G-protein-coupled receptor 120 and liver injury in children and adolescents with obesity

The G-protein-coupled receptor 120 (GPR120) is a receptor for polyunsaturated fatty acids with anti-inflammatory activity. The R270H variant of GPR120 enhances inflammation in adipose and hepatic tissues. We investigated whether the R270H variant could play a role in determining liver injury in children and adolescents with obesity. Five hundred eighty-one children with obesity were studied. No homozygotes and 20 heterozygotes for the 270H allele were found. Heterozygotes showed higher alanine transaminase (ALT) levels (P = 0.01) than wild-type subjects, and also showed an odds ratio to have pathologic ALT of 3.2 (95% confidence interval [CI] 1.2-8.0, P < 0.05). Moreover, we genotyped the same patients for the patatin-like phospholipase-containing domain 3 (PNPLA3) I148M polymorphism, which is implicated in the development of liver steatosis. Stratifying the patients with the GPR120 270H variant on the basis of their PNPLA3 polymorphism, we demonstrated a significant interaction effect on ALT levels (P = 0.00001), suggesting a driving effect of the PNPLA3 148M allele on liver injury in children with obesity carrying this variant.