Dietary Isoliquiritigenin at a Low Dose Ameliorates Insulin Resistance and NAFLD in Diet-Induced Obesity in C57BL/6J Mice

Isoliquiritigenin in combination with visceral adipose tissue and related markers as a predictive tool for nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent form of chronic liver disease in the world. New non-invasive diagnostic tools are needed to promptly treat this disease and avoid its complications. This study aimed to find key metabolites and related variables that could be used to predict and diagnose NAFLD. Ninety-eight subjects with NAFLD and 45 controls from the Fatty Liver in Obesity (FLiO) Study (NCT03183193) were analyzed. NAFLD was diagnosed and graded by ultrasound and classified into two groups: 0 (controls) and ≥ 1 (NAFLD). Hepatic status was additionally assessed through magnetic resonance imaging (MRI), elastography, and determination of transaminases. Anthropometry, body composition (DXA), biochemical parameters, and lifestyle factors were evaluated as well. Non-targeted metabolomics of serum was performed with high-performance liquid chromatography coupled to time-of-flight mass spectrometry (HPLC-TOF-MS). Isoliquiritigenin (ISO) had the strongest association with NAFLD out of the determinant metabolites. Individuals with higher concentrations of ISO had healthier metabolic and hepatic status and were less likely to have NAFLD (OR 0.13). Receiver operating characteristic (ROC) curves demonstrated the predictive power of ISO in panel combination with other NAFLD and IR-related variables, such as visceral adipose tissue (VAT) (AUROC 0.972), adiponectin (AUROC 0.917), plasmatic glucose (AUROC 0.817), and CK18-M30 (AUROC 0.810). Individuals with lower levels of ISO have from 71 to 82% more risk of presenting NAFLD compared to individuals with higher levels. Metabolites such as ISO, in combination with visceral adipose tissue, IR, and related markers, constitute a potential non-invasive tool to predict and diagnose NAFLD.

Natural Chalcones for the Management of Obesity Disease

In the last decade, the incidence of obesity has increased dramatically worldwide, reaching a dangerous pandemic spread. This condition has serious public health implications as it significantly increases the risk of chronic diseases such as type 2 diabetes, fatty liver, hypertension, heart attack, and stroke. The treatment of obesity is therefore the greatest health challenge of our time. Conventional therapeutic treatment of obesity is based on the use of various synthetic molecules belonging to the class of appetite suppressants, lipase inhibitors, hormones, metabolic regulators, and inhibitors of intestinal peptide receptors. The long-term use of these molecules is generally limited by various side effects and tolerance. For this reason, the search for natural alternatives to treat obesity is a current research goal. This review therefore examined the anti-obesity potential of natural chalcones based on available evidence from in vitro and animal studies. In particular, the results of the main in vitro studies describing the principal molecular therapeutic targets and the mechanism of action of the different chalcones investigated were described. In addition, the results of the most relevant animal studies were reported. Undoubtedly, future clinical studies are urgently needed to confirm and validate the potential of natural chalcones in the clinical prophylaxis of obesity.

Role of NLRP3 Inflammasome and Its Inhibitors as Emerging Therapeutic Drug Candidate for Alzheimer's Disease: a Review of Mechanism of Activation, Regulation, and Inhibition

Alzheimer's disease (AD) is one of the most prevalent neurodegenerative disorders. The etiology and pathology of AD are complicated, variable, and yet to be completely discovered. However, the involvement of inflammasomes, particularly the NLRP3 inflammasome, has been emphasized recently. NLRP3 is a critical pattern recognition receptor involved in the expression of immune responses and has been found to play a significant role in the development of various immunological and neurological disorders such as multiple sclerosis, ulcerative colitis, gout, diabetes, and AD. It is a multimeric protein which releases various cytokines and causes caspase-1 activation through the process known as pyroptosis. Increased levels of cytokines (IL-1β and IL-18), caspase-1 activation, and neuropathogenic stimulus lead to the formation of proinflammatory microglial M1. Progressive researches have also shown that besides loss of neurons, the pathophysiology of AD primarily includes amyloid beta (Aβ) accumulation, generation of oxidative stress, and microglial damage leading to activation of NLRP3 inflammasome that eventually leads to neuroinflammation and dementia. It has been suggested in the literature that suppressing the activity of the NLRP3 inflammasome has substantial potential to prevent, manage, and treat Alzheimer's disease. The present review discusses the functional composition, various models, signaling molecules, pathways, and evidence of NLRP3 activation in AD. The manuscript also discusses the synthetic drugs, their clinical status, and projected natural products as a potential therapeutic approach to manage and treat NLRP3 mediated AD.

Gut microbiota–mitochondrial inter-talk in non-alcoholic fatty liver disease

The increasing prevalence of non-alcoholic fatty liver disease (NAFLD), which is a progressive disease, has exerted huge a healthcare burden worldwide. New investigations have suggested that the gut microbiota closely participates in the progression of NAFLD through the gut–liver axis or gut–brain–liver axis. The composition of the microbiota can be altered by multiple factors, primarily dietary style, nutritional supplements, or exercise. Recent evidence has revealed that gut microbiota is involved in mitochondrial biogenesis and energy metabolism in the liver by regulating crucial transcription factors, enzymes, or genes. Moreover, microbiota metabolites can also affect mitochondrial oxidative stress function and swallow formation, subsequently controlling the inflammatory response and regulating the levels of inflammatory cytokines, which are the predominant regulators of NAFLD. This review focuses on the changes in the composition of the gut microbiota and metabolites as well as the cross-talk between gut microbiota and mitochondrial function. We thus aim to comprehensively explore the potential mechanisms of gut microbiota in NAFLD and potential therapeutic strategies targeting NAFLD management.

Liquorice root extract and isoliquiritigenin attenuate high-fat diet-induced hepatic steatosis and damage in rats by regulating AMPK

Objective: This study compared the ability of Liquorice roots aqueous extract (LRE) and its ingredient, isoliquiritigenin (ISL), in alleviating high-fat diet (HFD)-induced hepatic steatosis and examined if this effect involves activation of AMPK.Materials and methods: Control or HFD-fed rats were treated with the vehicle, LRE (200 mg/kg), or ISL (30 mg/kg) for 8 weeks orally.Results: ISL and LRE reduced HFD-induced hyperglycaemia, improved liver structure, lowered serum and hepatic lipids, and attenuated hepatic oxidative stress and inflammation. In the control and HFD-fed rats, ISL and LRE significantly stimulated the muscular and hepatic mRNA and protein levels of AMPK, improved oral glucose tolerance, reduced hepatic mRNA levels of SREBP1/2, and upregulated hepatic levels of PPARα and Bcl2. These effects were comparable for ISL and LRE and were prevented by co-administration of compound C, an AMPK inhibitor.Discussion and conclusion: ISL and LRE provide an effective theory to alleviate hepatic steatosis through activating AMPK.

Effects of magnesium picolinate, zinc picolinate, and selenomethionine co-supplementation on reproductive hormones, and glucose and lipid metabolism-related protein expressions in male rats fed a high-fat diet

This study aimed to examine the impacts of the magnesium picolinate (MgPic), zinc picolinate (ZnPic), and selenomethionine (SeMet) alone or as a combination on blood metabolites, oxidative enzymes, reproductive hormones, and glucose and lipid metabolism-related protein expressions in Wistar rats fed a high-fed diet (HFD). The rats were fed either a control, HFD, or HFD supplemented with a single (MgPic, ZnPic, SeMet) or two or three organic mineral combinations. Body weights, visceral fat, serum glucose, insulin, total cholesterol, triglycerides, leptin, malondialdehyde (MDA) concentrations as well as liver sterol regulatory element-binding protein-1c (SREBP-1c), liver X receptor alpha (LXRα), ATP citrate lyase (ACLY), fatty acid synthase (FAS), and nuclear factor kappa B (NF-κB) levels increased, while serum testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), and insulin-like growth factor (IGF-1) concentrations along with liver nuclear factor erythroid 2-related factor 2 (Nrf2) levels declined in HFD rats (P < 0.05). Supplementing each organic mineral, but particularly the combination of HFD + MgPic + ZnPic + SeMet reversed the responses with various degrees. None of the organic elements alone or as a combination of two exerted a prominent effect on parameters measured. Although not additive or synergistic, the combination of all organic minerals added to HFD (HFD + MgPic + ZnPic + SeMet) provided the greatest responses.

Bifidobacterium animalis ssp. lactis MG741 Reduces Body Weight and Ameliorates Nonalcoholic Fatty Liver Disease via Improving the Gut Permeability and Amelioration of Inflammatory Cytokines

Diet-induced obesity is one of the major causes of the development of metabolic disorders such as insulin resistance and nonalcoholic fatty liver disease (NAFLD). Recently, specific probiotic strains have been found to improve the symptoms of NAFLD. We examined the effects of Bifidobacterium animalis ssp. lactis MG741 (MG741) on NAFLD and weight gain, using a mouse model of high-fat-diet (HFD)-induced obesity. HFD-fed mice were supplemented daily with MG741. After 12 weeks, MG741-administered mice exhibited reduced fat deposition, and serum metabolic alterations, including fasting hyperinsulinemia, were modulated. In addition, MG741 regulated Acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), sterol regulatory element-binding protein 1 (SREBP-1), and carbohydrate-responsive element-binding protein (ChREBP) expression and lipid accumulation in the liver, thereby reducing the hepatic steatosis score. To determine whether the effects of MG741 were related to improvements in gut health, MG741 improved the HFD-induced deterioration in gut permeability by reducing toxic substances and inflammatory cytokine expression, and upregulating tight junctions. These results collectively demonstrate that the oral administration of MG741 could prevent NAFLD and obesity, thereby improving metabolic health.

Validation of a Quantification Method for Curcumin Derivatives and Their Hepatoprotective Effects on Nonalcoholic Fatty Liver Disease

Curcumin (CM), demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC) are major curcumin derivatives found in the rhizome of turmeric (Curcuma longa L.), and have yielded impressive properties to halt various diseases. In the present study, we carried out a method validation for curcumin derivatives and analyzed the contents simultaneously using HPLC with UV detection. For validation, HPLC was used to estimate linearity, range, specificity, accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ). Results showed a high linearity of the calibration curve, with a coefficient of correlation (R²) for CM, DMC, and BDMC of 0.9999, 0.9999, and 0.9997, respectively. The LOD values for CM, DMC, and BDMC were 1.16, 1.03, and 2.53 ng/μL and LOQ values were 3.50, 3.11, and 7.67 ng/μL, respectively. Moreover, to evaluate the ability of curcumin derivatives to reduce liver lipogenesis and compare curcumin derivatives’ therapeutic effects, a HepG2 cell model was established to analyze their hepatoprotective properties. Regarding the in vivo study, we investigated the effect of DMC, CM, and BDMC on nonalcoholic fatty liver disease (NAFLD) caused by a methionine choline deficient (MCD)-diet in the C57BL/6J mice model. From the in vitro and in vivo results, curcumin derivatives alleviated MCD-diet-induced lipid accumulation as well as high triglyceride (TG) and total cholesterol (TC) levels, and the protein and gene expression of the transcription factors related to liver adipogenesis were suppressed. Furthermore, in MCD-diet mice, curcumin derivatives suppressed the upregulation of toll-like receptors (TLRs) and the production of pro-inflammatory cytokines. In conclusion, our findings indicated that all of the three curcuminoids exerted a hepatoprotective effect in the HepG2 cell model and the MCD-diet-induced NAFLD model, suggesting a potential for curcuminoids derived from turmeric as novel therapeutic agents for NAFLD.

Direct CCL4 Inhibition Modulates Gut Microbiota, Reduces Circulating Trimethylamine N-Oxide, and Improves Glucose and Lipid Metabolism in High-Fat-Diet-Induced Diabetes Mellitus

Purpose

Modulation of the gut microbiota may lead to changes in pathological conditions. C-C chemokine motif ligand (CCL) 4 was upregulated in diabetes mellitus (DM) and was shown to play a significant role in pancreatic inflammation and glucose metabolism. The detailed in vivo mechanisms have not been well explored. This study aimed to investigate the hypothesis that direct CCL4 inhibition could modify gut microbiota and systemic metabolism in diet-induced DM mice.

Methods

C57BL/6 mice fed a high-fat diet (HFD) were used as a diet-induced DM model. CCL4 inhibition was conducted by anti-CCL4 neutralizing monoclonal antibodies. The gut microbiota was analyzed by high-throughput sequencing of the 16S rRNA. Fecal microbiota transplantation (FMT) was used to verify the effect of CCL4 deficiency on gut microbiota and the linkage between CCL4-modulated gut microbiota and HFD-induced DM.

Results

CCL4 inhibition stabilized glucose homeostasis, modulated lipid parameter, and decreased inflammatory markers in HFD-induced DM mice. Moreover, CCL4 inhibition reversed HFD-induced gut dysbiosis, evidenced by the decreased abundance of family Muribaculaceae and increased abundance of family Atopobiaceae when CCL4 antibodies were administrated. CCL4 inhibition led to a decrease in circulating trimethylamine N-oxide levels, a proinflammatory metabolite from gut microbiota. Taken together, CCL4 inhibition could modify gut microbiota profiles, suppress proinflammatory metabolites, reduce systemic inflammation, improve insulin resistance, and retard the progression of hyperglycemia in HFD-induced DM. Furthermore, FMT from CCL4 knockout mice rescued the glucose homeostasis in HFD-induced DM mice.

Conclusion

Our findings may not only provide a novel rationale to in vivo CCL4-based therapeutic approach in diet-induced DM but also indicate the significance of gut microbiota profile including the family Muribaculaceae and the family Atopobiaceae as a potential modifiable target for systemic metabolism.

Modulation of the fecal microbiome and metabolome by resistant dextrin ameliorates hepatic steatosis and mitochondrial abnormalities in mice

Targeting the gut-liver axis by manipulating the intestinal microbiome is a promising therapy for nonalcoholic fatty liver disease (NAFLD). This study modulated the intestinal microbiota to explore whether resistant dextrin, as a potential prebiotic, could ameliorate high-fat diet (HFD)-induced hepatic steatosis in C57BL/6J mice. After two months of feeding, significant hepatic steatosis with mitochondrial dysfunction was observed in the HFD-fed mice. However, the concentrations of triglycerides and malondialdehyde in liver tissue and the levels of alanine aminotransferase and aspartate aminotransferase in the serum of mice fed an HFD plus resistant dextrin diet (HFID) were significantly decreased compared to the HFD-fed mice. Additionally, hepatic mitochondrial integrity and reactive oxygen species accumulation were improved in HFID-fed mice, ameliorating hepatic steatosis. The fecal microbiome of HFD-fed mice was enriched in Bifidobacterium, Lactobacillus, and Globicatella, while resistant dextrin increased the abundance of Parabacteroides, Blautia, and Dubosiella. Major changes in fecal metabolites were confirmed for HFID-fed mice, including those related to entero-hepatic circulation (i.e., bile acids), tryptophan metabolism (e.g., indole derivatives), and lipid metabolism (e.g., lipoic acid), as well as increased antioxidants including isorhapontigenin. Furthermore, resistant dextrin decreased inflammatory cytokine levels and intestinal permeability and ameliorated intestinal damage. Together, these findings augmented current knowledge on prebiotic treatment for NAFLD.

Administration of isoliquiritigenin prevents nonalcoholic fatty liver disease through a novel IQGAP2-CREB-SIRT1 axis

Isoliquiritigenin (ISO) is a flavonoid extracted from the root of licorice, which serves various biological and pharmacological functions including antiinflammatory, antioxidation, liver protection, and heart protection. However, the mechanism of its action remains elusive and the direct target proteins of ISO have not been identified so far. Through cell-based screening, we identified ISO as a potent lipid-lowering compound. ISO treatment successfully ameliorated fatty acid-induced cellular lipid accumulation and improved nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) by increasing PPARα-dependent lipid oxidation and decreasing SREBPs-dependent lipid synthesis. Both these signaling required the activation of SIRT1. Knockdown of SIRT1 resulted in the reversal of ISO beneficiary effects suggesting that the lipid-lowering activity of ISO was regulated by SIRT1 expression. To identify the direct target of ISO, limited proteolysis combined with mass spectrometry (LiP-SMap) strategy was applied and IQGAP2 was identified as the direct target for ISO in regulating lipid homeostasis. In the presence of ISO, both mRNA and protein levels of SIRT1 were increased; however, this effect was abolished by blocking IQGAP2 expression using siRNA. To explore how IQGAP2 regulated the expression level of SIRT1, proteome profiler human phospho-kinase array kit was used to reveal possible phosphorylated kinases and signaling nodes that ISO affected. We found that through phosphorylation of CREB, ISO transduced signals from IQGAP2 to upregulate SIRT1 expression. Thus, we not only demonstrated the molecular basis of ISO in regulating lipid metabolism but also exhibited for the first time a novel IQGAP2-CREB-SIRT1 axis in treating NAFLD/NASH.

Isoliquiritigenin attenuates inflammation and modulates Nrf2/caspase-3 signalling in STZ-induced aortic injury

OBJECTIVES

The current study provides evidence on the ameliorative impact of Isoliquiritigenin (ISL), a natural bioflavonoid isolated from licorice roots against diabetes mellitus (DM)-induced aortic injury in rats.

METHODS

DM was induced in male Sprague-Dawley rats by single I.P. injection of STZ (50 mg/kg). ISL was administrated daily (20 mg/kg, orally) for 8 wks.

KEY FINDINGS

Diabetic group showed a significant aortic injury with evidence of atherosclerotic lesions development. Daily ISL (20 mg/kg, orally) administration for 8 wks significantly restored aortic oxidative/antioxidative stress homeostasis via modulating NrF-2/Keap-1/HO-1. Moreover, ISL treatment restored aortic levels of IL-10 and dampened aortic levels of IL-6 and TNF-α. Caspase-3 expression significantly declined as well. Further, ISL treatment successfully suppressed aortic endothelin-1 (ET-1) expression and restored NO contents, eNOS immunostaining paralleled with retraction in atherosclerotic lesions development, and lipid deposition with histopathological architectural preservation and restoration of almost normal aortic thickness.

CONCLUSION

ISL can be proposed to be an effective protective therapy to prevent progression of DM-induced vascular injury and to preserve aortic integrity.

A lupine (Lupinus angustifolious L.) peptide prevents non-alcoholic fatty liver disease in high-fat-diet-induced obese mice

Bioactive peptides are related to the prevention and treatment of many diseases. GPETAFLR is an octapeptide that has been isolated from lupine (Lupinus angustifolius L.) and shows anti-inflammatory properties. The aim of this study was to evaluate the potential activity of GPETAFLR to prevent non-alcoholic fatty liver disease (NAFLD) in high-fat-diet (HFD)-induced obese mice. C57BL/6J mice were fed a standard diet or HFD. Two of the groups fed the HFD diet were treated with GPETAFLR in drinking water at 0.5 mg kg-1 day-1 or 1 mg kg-1 day-1. To determine the ability of GPETAFLR to improve the onset and progression of non-alcoholic fatty liver disease, histological studies, hepatic enzyme profiles, inflammatory cytokine and lipid metabolism-related genes and proteins were analysed. Our results suggested that HFD-induced inflammatory metabolic disorders were alleviated by treatment with GPETAFLR. In conclusion, dietary lupine consumption can repair HFD-induced hepatic damage possibly via modifications of liver's lipid signalling pathways.

Anti-NLRP3 Inflammasome Natural Compounds: An Update

The nucleotide-binding domain and leucine-rich repeat related (NLR) family, pyrin domain containing 3 (NLRP3) inflammasome is a multimeric protein complex that recognizes various danger or stress signals from pathogens, the host, and the environment, leading to activation of caspase-1 and inducing inflammatory responses. This pro-inflammatory protein complex plays critical roles in pathogenesis of a wide range of diseases including neurodegenerative diseases, autoinflammatory diseases, and metabolic disorders. Therefore, intensive efforts have been devoted to understanding its activation mechanisms and to searching for its specific inhibitors. Approximately forty natural compounds with anti-NLRP3 inflammasome properties have been identified. Here, we provide an update about new natural compounds that have been identified within the last three years to inhibit the NLRP3 inflammasome and offer an overview of the underlying molecular mechanisms of their anti-NLRP3 inflammasome activities.

Isoliquiritigenin Enhances the Beige Adipocyte Potential of Adipose-Derived Stem Cells by JNK Inhibition

Human adipose-derived stem cells (hASCs) can be isolated from fat tissue and have attracted interest for their potential therapeutic applications in metabolic disease. hASCs can be induced to undergo adipogenic differentiation in vitro by exposure to chemical agents or inductive growth factors. We investigated the effects and mechanism of differentiating hASC-derived white adipocytes into functional beige and brown adipocytes with isoliquiritigenin (ILG) treatment. Here, we showed that hASC-derived white adipocytes could promote brown adipogenesis by expressing both uncoupling protein 1 (UCP1) and PR/SET Domain 16 (PRDM16) following low-dose ILG treatments. ILG treatment of white adipocytes enhanced the expression of brown fat-specific markers, while the expression levels of c-Jun N-terminal kinase (JNK) signaling pathway proteins were downregulated. Furthermore, we showed that the inhibition of JNK phosphorylation contributed to white adipocyte differentiation into beige adipocytes, which was validated by the use of SP600125. We identified distinct regulatory effects of ILG dose responses and suggested that low-dose ILG induced the beige adipocyte potential of hASCs via JNK inhibition.

Interactions between leptin and insulin resistance in patients with prediabetes, with and without NAFLD

This study explored the link between insulin sensitivity, insulin resistance and leptinaemia in people with prediabetes with and without non-alcoholic fatty liver disease (NAFLD). A total of 143 prediabetes patients were evaluated in the study. Ultrasonography was used for diagnosis of NAFLD, and fasting insulin, postprandial insulin, leptin levels, common clinical/biochemical determinations were determined. In total, 69 (48.25%) of the patients were diagnosed with NAFLD and 74 (51.75%) without NAFLD. Leptin values correlated statistically with fasting insulin in prediabetes patients, while in the patients that were also diagnosed with NAFLD the correlation was stronger. Values of log-leptin <1 ng/ml were found in 64% of patients with prediabetes without NAFLD, and in 2% of patients with prediabetes and NAFLD. In the context of the association between serum leptin levels and a worse biochemical profile in prediabetes patients on one hand, and fatty liver disease and a worse biochemical profile in prediabetes patients on the other, leptin can be considered a possible candidate molecule that mediates the biochemical alterations identified in these patients.

Metabolic Impact of Flavonoids Consumption in Obesity: From Central to Peripheral

The prevention and treatment of obesity is primary based on the follow-up of a healthy lifestyle, which includes a healthy diet with an important presence of bioactive compounds such as polyphenols. For many years, the health benefits of polyphenols have been attributed to their anti-oxidant capacity as free radical scavengers. More recently it has been described that polyphenols activate other cell-signaling pathways that are not related to ROS production but rather involved in metabolic regulation. In this review, we have summarized the current knowledge in this field by focusing on the metabolic effects of flavonoids. Flavonoids are widely distributed in the plant kingdom where they are used for growing and defensing. They are structurally characterized by two benzene rings and a heterocyclic pyrone ring and based on the oxidation and saturation status of the heterocyclic ring flavonoids are grouped in seven different subclasses. The present work is focused on describing the molecular mechanisms underlying the metabolic impact of flavonoids in obesity and obesity-related diseases. We described the effects of each group of flavonoids in liver, white and brown adipose tissue and central nervous system and the metabolic and signaling pathways involved on them.

Combined Treatment with L-Carnitine and Nicotinamide Riboside Improves Hepatic Metabolism and Attenuates Obesity and Liver Steatosis

Obesity characterized by adiposity and ectopic fat accumulation is associated with the development of non-alcoholic fatty liver disease (NAFLD). Treatments that stimulate lipid utilization may prevent the development of obesity and comorbidities. This study evaluated the potential anti-obesogenic hepatoprotective effects of combined treatment with L-carnitine and nicotinamide riboside, i.e., components that can enhance fatty acid transfer across the inner mitochondrial membrane and increase nicotinamide adenine nucleotide (NAD+) levels, which are necessary for β-oxidation and the TCA cycle, respectively. Ldlr -/-.Leiden mice were treated with high-fat diet (HFD) supplemented with L-carnitine (LC; 0.4% w/w), nicotinamide riboside (NR; 0.3% w/w) or both (COMBI) for 21 weeks. L-carnitine plasma levels were reduced by HFD and normalized by LC. NR supplementation raised its plasma metabolite levels demonstrating effective delivery. Although food intake and ambulatory activity were comparable in all groups, COMBI treatment significantly attenuated HFD-induced body weight gain, fat mass gain (-17%) and hepatic steatosis (-22%). Also, NR and COMBI reduced hepatic 4-hydroxynonenal adducts. Upstream-regulator gene analysis demonstrated that COMBI reversed detrimental effects of HFD on liver metabolism pathways and associated regulators, e.g., ACOX, SCAP, SREBF, PPARGC1B, and INSR. Combination treatment with LC and NR exerts protective effects on metabolic pathways and constitutes a new approach to attenuate HFD-induced obesity and NAFLD.