L-carnitine ameliorates the liver inflammatory response by regulating carnitine palmitoyltransferase I-dependent PPARγ signaling

Pea Albumin Extracted from Pea (Pisum sativum L.) Seeds Ameliorates High-Fat-Diet-Induced Non-Alcoholic Fatty Liver Disease by Regulating Lipogenesis and Lipolysis Pathways

Non-alcoholic fatty liver disease (NAFLD) is now recognized as the most prevalent liver disease globally. Pea albumin (PA) has demonstrated positive impacts on reducing obesity and improving glucose metabolism. In this research, a mouse model of NAFLD induced by a high-fat diet (HFD) was employed to examine the impact of PA on NAFLD and explore its potential mechanisms. The findings revealed that mice subjected to a HFD developed pronounced fatty liver alterations. The intervention with PA significantly lowered serum TC by 26.81%, TG by 43.55%, and LDL-C by 57.79%. It also elevated HDL-C levels by 1.2 fold and reduced serum ALT by 37.94% and AST by 31.21% in mice fed a HFD. These changes contributed to the reduction in hepatic steatosis and lipid accumulation. Additionally, PA improved insulin resistance and inhibited hepatic oxidative stress and inflammatory responses. Mechanistic studies revealed that PA alleviated lipid accumulation in HFD-induced NAFLD by activating the phosphorylation of AMPKα and ACC, inhibiting the expression of SREBF1 and FASN to reduce hepatic lipogenesis, and increasing the expression of ATGL, PPARα, and PPARγ to promote lipolysis and fatty acid oxidation. These results indicate that PA could serve as a dietary supplement for alleviating NAFLD, offering a theoretical foundation for the rational intake of PA in NAFLD intervention.

From genes to systems: The role of food supplementation in the regulation of sepsis-induced inflammation

Systemic inflammation includes a widespread immune response to a harmful stimulus that results in extensive systemic damage. One common example of systemic inflammation is sepsis, which is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Under the pro-inflammatory environment of sepsis, oxidative stress contributes to tissue damage due to dysfunctional microcirculation that progressively causes the failure of multiple organs that ultimately triggers death. To address the underlying inflammatory condition in critically ill patients, progress has been made to assess the beneficial effects of dietary supplements, which include polyphenols, amino acids, fatty acids, vitamins, and minerals that are recognized for their immuno-modulating, anticoagulating, and analgesic properties. Therefore, we aimed to review and discuss the contribution of food-derived supplementation in the regulation of inflammation from gene expression to physiological responses and summarize the precedented potential of current therapeutic approaches during systemic inflammation.

Investigation of L-carnitine effects on CD44+ cancer stem cells from MDA-MB-231 breast cancer cell line as anti-cancer therapy

Breast cancer stem cells (BCSCs) are a small subpopulation of breast cancer cells, capable of metastasis, recurrence, and drug resistance in breast cancer patients. Therefore, targeting BCSCs appears to be a promising strategy for the treatment and prevention of breast cancer metastasis. Mounting evidence supports the fact that carnitine, a potent antioxidant, modulates various mechanisms by enhancing cellular respiration, inducing apoptosis, and reducing proliferation and inflammatory responses in tumor cells. The objective of this study was to investigate the impact of L-carnitine (LC) on the rate of proliferation and induction of apoptosis in CD44⁺ CSCs. To achieve this, the CD44⁺ cells were enriched using the Magnetic-activated cell sorting (MACS) isolation method, followed by treatment with LC at various concentrations. Flow cytometry analysis was used to determine cell apoptosis and proliferation, and western blotting was performed to detect the expression levels of proteins. Treatment with LC resulted in a significant decrease in the levels of p-JAK2, p-STAT3, Leptin receptor, and components of the leptin pathway. Moreover, CD44⁺ CSCs-treated cells with LC exhibited a reduction in the proliferation rate, accompanied by an increase in the percentage of apoptotic cells. Hence, it was concluded that LC could potentially influence the proliferation and apoptosis of CD44⁺ CSC by modulating the expression levels of specific protein.

The beneficial effects of l-carnitine and infliximab in methotrexate-induced hepatotoxicity: Emphasis on Notch1/Hes-1 signaling

Methotrexate (MTX)-induced hepatotoxicity is a serious adverse effect that may limit its use. Therefore, eligible drugs to ameliorate MTX-induced hepatotoxicity are required. l-Carnitine (LC) is a natural molecule with beneficial metabolic effects and infliximab (INF) is an anti-inflammatory monoclonal antibody against tumor necrosis factor-alpha (TNF-α). Recently, Notch1/Hes-1 signaling was found to play a key role in the pathogenesis of liver injury. However, its role in MTX-induced hepatotoxicity is unclear. This study aimed to evaluate the modulatory effects of LC or INF on MTX-induced hepatotoxicity and to explore the underlying mechanism with emphasis on the Notch1/Hes-1 signaling pathway. Sixty rats were randomized into six groups (n = 10): (1) control (saline); (2) MTX (20 mg/kg MTX, intraperitoneal [ip], once); (3) LC group (500 mg/kg ip, 5 days); (4) INF (7 mg/kg INF ip, once); (5) MTX+LC (20 mg/kg ip, once, 500 mg/kg ip, 5 days, respectively); (6) MTX+INF (20 mg/kg ip, once, 7 mg/kg INF ip, once, respectively). Oxidative stress, inflammatory markers, and Notch1/Hes-1 were investigated. MTX induced the expression of Notch1 and Hes-1 proteins and increased the levels of TNF-α, interleukin (IL)-6, and IL-1β in the liver. Cotreatment with LC or INF showed apparent antioxidant and anti-inflammatory effects. Interestingly, the downregulation of Notch1 and Hes-1 expression was more prominent in LC cotreatment as compared with INF. In conclusion, LC or INF attenuates MTX-induced hepatotoxicity through modulation of Notch1/Hes-1 signaling. The LC ameliorative effect against MTX-induced hepatotoxicity is significantly better than that of INF. Therefore, LC cotreatment may present a safe and therapeutically effective therapy in alleviating MTX-induced hepatotoxicity.

L-carnitine reverses methotrexate-induced nephrotoxicity in experimental rat model: Insight on SIRT1/PGC-1α/Nrf2/HO-1 axis

Methotrexate (MTX) is a chemotherapeutic agent used for treating several types of cancer as well as psoriasis and rheumatoid arthritis, but its use is limited due to its nephrotoxicity. The purpose of this research work was to observe ameliorative effects of L-carnitine (LC) toward renal toxicity caused by MTX and mechanisms responsible for these effects. Thirty-two male Sprague-Dawley rats were divided into four groups (eight rats/group), control group (received saline), MTX group (20 mg/kg/i.p. once), LC group (500 mg/kg/i.p. for 5 days), and MTX + LC group (received a single MTX dose 20 mg/kg/i.p. followed by LC 500 mg/kg/i.p. for 5 days). Histopathological examinations, lipid oxidation marker, malondialdehyde (MDA), and the antioxidant superoxide dismutase (SOD) as well as inflammatory (tumor necrosis factor-α [TNF-α] and interleukin-6 [IL-6]) and apoptotic markers (Bax, Bcl2, and caspase-3) were used to assess renal toxicity. Moreover, the protein levels of silent information regulator 1 (SIRT1) and its downstream signaling targets, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), and nuclear factor erythroid 2-related factor 2 (Nrf2) in addition to heme oxygenase-1 (HO-1) were measured. LC significantly protected against MTX-induced nephrotoxicity. It ameliorated MTX-induced renal histopathological changes and diminished MTX-induced renal oxidative stress, renal inflammation, and apoptosis. LC also upregulated the expression of SIRT1 and PGC-1 as well as Nrf2 and HO-1. By controlling the expression of renal SIRT1/PGC-1/Nrf2/HO-1, LC displayed antioxidant, anti-inflammatory, and anti-apoptotic activities. Hence, using LC supplements may help prevent negative MTX side effects.

Defatting of Human Livers During Long-Term e x situ Normothermic Perfusion: Novel Strategy to Rescue Discarded Organs for Transplantation

OBJECTIVE

To develop a protocol for the defatting of steatotic liver grafts during long-term ex situ normothermic machine perfusion.

BACKGROUND

Despite the alarming increase in donor organ shortage, the highly prevalent fatty liver grafts are often discarded due to the risk of primary nonfunction. Effective strategies preventing such outcomes are currently lacking. An exciting new avenue is the introduction of ex situ normothermic machine perfusion (NMP), enabling a liver to remain fully functional for up to 2 weeks and providing a unique window of opportunity for defatting before transplantation.

METHODS

Over a 5-year period, 23 discarded liver grafts and 28 partial livers from our resection program were tested during ex situ normothermic machine perfusion. The steatosis degree was determined on serial biopsies by expert pathologists, and triglyceride contents were measured simultaneously.

RESULTS

Of 51 liver grafts, 20 were steatotic, with up to 85% macrovesicular steatosis, and were perfused for up to 12 days. Ten livers displayed marked (5 of which almost complete) loss of fat, while the other 10 did not respond to long-term perfusion. Successful defatting was related to prolonged perfusion, automated glucose control, circadian nutrition, and L-carnitine/fenofibrate supplementation. Pseudopeliotic steatosis and the associated activation of Kupffer/stellate cells were unexpected processes that might contribute to defatting. Synthetic and metabolic functions remained preserved for most grafts until perfusion ended.

CONCLUSION

Ex situ long-term perfusion effectively reduces steatosis while preserving organ viability and may in the future allow transplantation of primarily unusable high-risk grafts, significantly increasing the number of organs available for transplantation.

The effect of L-carnitine supplementation on lipid profile in adults: an umbrella meta-analysis on interventional meta-analyses

Introduction

Previous meta-analyses investigating the therapeutic effects of L-carnitine on lipid profiles have demonstrated inconsistent results. The present umbrella meta-analysis aimed to investigate the impact of efficacy of L-carnitine on lipid profiles in adults.

Methods

Databases including PubMed, Scopus, and Embase, Web of Science, and Google Scholar were searched up to June 2023. Meta-analysis was performed using a random-effects model.

Results

Our results from thirteen meta-analyses indicated that L-carnitine supplementation significantly total cholesterol (TC) (ES = -1.05 mg/dL, 95% CI: -1.71, -0.39; p = 0.002), triglycerides (TG) (ES = -2.51 mg/dL; 95% CI: -3.62, -1.39, p < 0.001), and low-density lipoprotein-cholesterol (LDL-C) (ES = -4.81 mg/dL; 95% CI: -6.04, -3.59; p < 0.001). It also increased high-density lipoprotein-cholesterol (HDL-C) (ES: 0.66 mg/dL, 95% CI: 0.20, 1.12, p = 0.005) levels.

Conclusion

The present umbrella meta-analysis suggests supplementation with L-carnitine in a dosage of more than 2 g/day can improve lipid profile. Thus, L-carnitine supplementation can be recommended as an adjuvant anti-hyperlipidemic agent.

L-Carnitine and synbiotic co-supplementation: beneficial effects on metabolic-endotoxemia, meta-inflammation, and oxidative-stress biomarkers in obese patients: a double blind, randomized, controlled clinical trial

Obesity, a chronic pandemic disease, is characterized by low-grade chronic inflammation, accompanied by over-expression of pro-inflammatory cytokines, thereby contributing to metabolic disorders pathogenesis. Oxidative-stress, an adverse cellular response to adipocyte hypertrophy, promotes inflammation. Furthermore, gut-microbiota dysbiosis may induce oxidative-stress, low-grade inflammation, and metabolic-endotoxemia as major drivers of obesity. Functional-foods/nutraceuticals have attracted extensive attention due to their plausible anti-inflammatory/anti-oxidative properties; evidence supports the superiority of the nutraceutical combined-supplementation approach versus conventional mono-therapies. Current data suggest the anti-oxidative/anti-inflammatory properties of either L-carnitine or pre/pro/synbiotics. This trial compared the effects of co-supplementing L-carnitine and multi-species/multi-strain synbiotic versusL-carnitine mono-therapy on inflammatory/anti-inflammatory, oxidative-stress, and metabolic-endotoxemia biomarkers in 46 female obese patients, receiving either co-supplementation (L-carnitine-tartrate (2 × 500 mg d^-1) + multi-species/multi-strain synbiotic (1 capsule per day)) or mono-therapy (L-carnitine-tartrate (2 × 500 mg d^-1) + maltodextrin (1 capsule per day)) for eight weeks. L-Carnitine + synbiotic co-supplementation significantly decreased interleukin-6 (IL-6, -33.98%), high-sensitivity-C-reactive-protein (hs-CRP, -10%), tumor-necrosis-factor-alpha (TNF-α, -18.73%), malondialdehyde (MDA, -21.73%), and lipopolysaccharide (LPS, -10.14%), whereas the increase in interleukin-10 (IL-10, 7.69%) and total-antioxidant-capacity (TAC, 4.13%) levels was not significant. No significant changes were observed for the above-mentioned parameters in the L-carnitine + placebo group, except for a significant reduction in IL-10 (-17.59%) and TNF-α (-14.78%); however, between-group differences did not reach the significant threshold. Co-supplementing L-carnitine + multi-strain synbiotic led to significant amelioration of inflammatory, oxidative, and metabolic-endotoxemia responses in female obese patients; nevertheless, no improving effects were observed in patients receiving single-supplementation, suggesting that L-carnitine + synbiotic co-supplementation might represent an adjuvant approach to improve oxidative-stress/pro-inflammatory indicators in women with obesity, possibly through beneficial effects of the synbiotic alone. Further longer duration studies with higher doses of L-carnitine in a three-group setting are warranted to elucidate the possibility of synergistic or complementary mechanisms.

Normalization of lipid oxidation defects arising from hypoxia early posthepatectomy prevents liver failure in mouse

Surgical liver failure (SLF) develops when a marginal amount of hepatic mass is left after surgery, such as following excessive resection. SLF is the commonest cause of death due to liver surgery; however, its etiology remains obscure. Using mouse models of standard hepatectomy (sHx) (68%, resulting in full regeneration) or extended hepatectomy (eHx) (86%/91%, causing SLF), we explored the causes of early SLF related to portal hyperafflux. Assessing the levels of HIF2A with or without oxygenating agent inositol trispyrophosphate (ITPP) indicated hypoxia early after eHx. Subsequently, lipid oxidation (PPARA/PGC1α) was downregulated and associated with persisting steatosis. Mild oxidation with low-dose ITPP reduced the levels of HIF2A, restored downstream PPARA/PGC1α expression along with lipid oxidation activities (LOAs), and normalized steatosis and other metabolic or regenerative SLF deficiencies. Promotion of LOA with L-carnitine likewise normalized the SLF phenotype, and both ITPP and L-carnitine markedly raised survival in lethal SLF. In patients who underwent hepatectomy, pronounced increases in serum carnitine levels (reflecting LOA) were associated with better recovery. Lipid oxidation thus provides a link between the hyperafflux of O₂-poor portal blood, the metabolic/regenerative deficits, and the increased mortality typifying SLF. Stimulation of lipid oxidation-the prime regenerative energy source-particularly through L-carnitine may offer a safe and feasible way to reduce SLF risks in the clinic.

Biomedical role of L-carnitine in several organ systems, cellular tissues, and COVID-19

Carnitine is a conditionally necessary vitamin that aids in energy creation and fatty acid metabolism. Its bioavailability is higher in vegetarians than in meat-eaters. Deficits in carnitine transporters occur because of genetic mutations or in conjunction with other illnesses. Carnitine shortage can arise in health issues and diseases-including hypoglycaemia, heart disease, starvation, cirrhosis, and ageing-because of abnormalities in carnitine control. The physiologically active form of L-carnitine supports immunological function in diabetic patients. Carnitine has been demonstrated to be effective in the treatment of Alzheimer's disease, several painful neuropathies, and other conditions. It has been used as a dietary supplement for the treatment of heart disease, and it also aids in the treatment of obesity and reduces blood glucose levels. Therefore, L-carnitine shows the potential to eliminate the influences of fatigue in COVID-19, and its consumption is recommended in future clinical trials to estimate its efficacy and safety. This review focused on carnitine and its effect on tissues, covering the biosynthesis, metabolism, bioavailability, biological actions, and its effects on various body systems and COVID-19.

L-Carnitine improves follicular survival and function in ovarian grafts in the mouse

CONTEXT

Ovarian tissue transplantation is performed to preserve fertility in patients undergoing chemotherapy and radiotherapy. However, the ischemia-reperfusion injury which occurs after the ovarian tissue transplantation causes follicular depletion and apoptosis. l -Carnitine has antioxidant and anti-inflammation properties.

AIMS

Therefore, we aimed to investigate the beneficial effect of l -carnitine on mouse ovaries following heterotopic autotransplantation.

METHODS

Mice were randomly divided into three groups (six mice per group): control, autografted and autografted+l -carnitine (200mg/kg daily intraperitoneal injections). Seven days after ovary autografting, the serum levels of malondialdehyde (MDA), total antioxidant capacity, tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-10 were measured. Ovary histology, serum concentrations of progesterone and estradiol were also measured 28days after autotransplantation. Data were analysed using one-way analysis of variance (ANOVA) and Tukey test, and the means were considered significantly different at P Key results: In the autografted+l -carnitine group, the total volume of the ovary, the volume of the cortex, the number of follicles, the serum concentrations of IL-10, estradiol and progesterone significantly increased compared to the autografted group. In the autografted+l -carnitine group, serum concentrations of IL-6, TNF-α and MDA were significantly decreased compared to the autografted group.

CONCLUSIONS

Our results indicated that l -carnitine can ameliorate the consequences of ischemia-reperfusion on the mice ovarian tissue following autotransplantation.

IMPLICATIONS

l -carnitine improves the structure and function of transplanted ovaries.

The effects of L-carnitine supplementation on inflammatory factors, oxidative stress, and clinical outcomes in patients with sepsis admitted to the intensive care unit (ICU): study protocol for a double blind, randomized, placebo-controlled clinical trial

BACKGROUND

Sepsis is a common cause for admission to the intensive care unit (ICU), and its incidence has been increasing. It is associated with a significant increase in serum inflammatory biomarkers such as C-reactive protein (CRP) and cytokines such as interleukin 1 (IL-1), IL-6, and tumor necrosis factor (TNF). Sepsis is also associated with pathophysiological changes that include fluid accumulation in the lungs, eventually leading to acute respiratory distress syndrome (ARDS), tissue edema, hypotension, and acute kidney injury (AKI). Conventional therapies include antibiotics, but these may have important adverse effects, so novel therapeutic approaches are required. In animal studies, L-carnitine improves antioxidant status, and in some clinical trials, it has been shown to reduce inflammation. It has also been shown to improve respiratory distress and help maintain coenzyme A homeostasis, metabolic flexibility, promoting the normal function of the tricarboxylic acid (TCA) cycle, and oxidation of fatty acids by peroxisomes. We aim to determine the effects of very high doses of L-carnitine on inflammatory factors, oxidative stress, and clinical outcomes of patients with sepsis in ICU.

METHOD AND DESIGN

In this double-blind, randomized controlled clinical trial, we will use block randomization of 60 patients with sepsis, aged between 20 and 65 years from Al-Zahra Hospital, Isfahan, Iran. The intervention group (n = 30) will receive three capsules of L-carnitine (each capsule contains 1000 mg L-carnitine; totally 3000 mg/day) for 7 days, and a control group (n = 30) will receive a placebo with the same dose and for the same duration in addition to usual care. At baseline, scores for clinical and nutritional status (Acute Physiology and Chronic Health Evaluation II (APACHE II), Sequential Organ Failure Assessment (SOFA), Quick SOFA (qSOFA), and NUTRIC Score) will be assessed. At beginning and end point of the study, inflammatory markers (CRP, erythrocyte sedimentation rate (ESR)), oxidative stress status (total oxidative stress (TOS), total antioxidant capacity (TAC)), and clinical variables will be evaluated also. The mortality rate will be assessed within 28 days of the beginning of the intervention.

DISCUSSION

Because of the anti-inflammatory and antioxidant properties of L-carnitine, it is possible that using a high dose of 3000 mg daily of this nutritional supplement may reduce inflammation and oxidative stress and improve subsequent mortality of critically ill patients with sepsis.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20201129049534N1 . Registered on 2 May 2021.

Peripartal Rumen-Protected L-Carnitine Manipulates the Productive and Blood Metabolic Responses in High-Producing Holstein Dairy Cows

This study aimed to monitor the effect of including rumen-protected L-carnitine (Carneon 20 Rumin-Pro, Kaesler Nutrition GmbH, Cuxhaven, Germany) in the transition diet on the productive and metabolic responses of multiparous high-producing Holstein dairy cows. Thirty-two multiparous cows were allocated in a completely randomized design to receive the same diet plus 60 g fat prill containing 85% palmitic acid (control, n = 16) or 100 g rumen-protected L-carnitine (RLC, n = 16); at 28 days before expected calving until 28 days in milk (DIM). Fat prill was included in the control diet to balance the palmitic acid content of both experimental diets. Milk production over the 28 DIM for the control and RLC groups was 46.5 and 47.7 kg, respectively. Milk fat content tended to increase upon rumen-protected L-carnitine inclusion (p = 0.1). Cows fed rumen-protected L-carnitine had higher fat- and energy-corrected milk compared with the control group. Pre- and post-partum administration of L-carnitine decreased both high- and low-density lipoprotein concentrations in peripheral blood of post-partum cows. The results of this study indicated that the concentration of triglycerides and beta-hydroxybutyrate was not significantly different between the groups, whereas the blood non-esterified fatty acid concentration was markedly decreased in cows supplemented with L-carnitine. Animals in the RLC group had a significant (p < 0.05) lower blood haptoglobin concentration at 7 and 14 DIM than the control. Animals in the RLC group had a lower concentration of blood enzymes than those of the control group. The mRNA abundance of Toll-like receptors 4, cluster of differentiation 14, and myeloid differential protein 2 did not significantly change upon the supplementation of L-carnitine in the transition diet. In summary, the dietary inclusion of RLC improved dairy cow's performance during the early lactation period. Greater production, at least in part, is driven by improved energy utilization efficiency and enhanced metabolic status in animals during the periparturient period.

Effect of l-carnitine supplementation on lead acetate-induced liver cell apoptosis and inflammation: role of caspase-3 and glycogen synthase kinase-3β enzymes

AIM

The study aimed at studying the hepatoprotective effect of l-carnitine against lead (Pb) acetate-induced hepatocellular injury, emphasizing the role of caspase-3 and glycogen synthase kinase-3β in hepatocellular apoptosis and inflammation.

MATERIALS AND METHODS

Male Wistar rats were used. The experimental approach involved estimation of the liver enzymes' serum levels. Oxidative and inflammatory biomarkers were measured in hepatic tissue homogenates. Paraffin-embedded hepatic sections were prepared for histopathology and immunohistochemistry. Quantitative determination of the phosphorylated glycogen synthase kinase-3 beta was performed.

KEY FINDINGS

The serum showed a significant elevation in ALT, AST, and LDH; tissue homogenates showed significant elevation in lipid peroxide and inflammatory biomarkers with significant reduction in reduced glutathione in the Pb acetate-treated group. Co-administration of l-carnitine with Pb acetate produced significant reduction in liver enzymes with significant improvement in oxidant, antioxidant and inflammatory markers. Lead acetate treatment significantly reduced the phosphorylated glycogen synthase kinase-3 beta, while l-carnitine enhanced its phosphorylation. Histopathological examination showed inflammatory reaction around blood vessels with fatty degeneration in hepatocytes of the Pb acetate intoxicated group. l-Carnitine caused a decrease in hepatic damage with minimal vascular alterations in central vein. Caspase-3 expression in hepatocytes was decreased in Pb-treated group supplemented with l-carnitine.

SIGNIFICANCE

Our study reveals that oxidative stress and inflammation participate in Pb acetate-induced hepatocellular injury. Glycogen synthase kinase-3β and caspase-3 play role in Pb acetate-induced hepatic damage. l-Carnitine shows significant protective effects against hepatocellular apoptosis and inflammation induced by Pb acetate through antioxidant, anti-inflammatory and anti-apoptotic pathways in part mediated by GSK-3β inhibition.

Comprehensive assessment of the effectiveness of l-carnitine and transresveratrol in rats with diet-induced obesity

OBJECTIVES

Transresveratrol (Res) and l-carnitine (l-Car) are proposed to alleviate metabolic and immune disorders and increase physical activity in obese individuals. This study aims to estimate the effect of Res and l-Car in rats with diet-induced obesity.

METHODS

Male Wistar rats were fed a diet with excess fat and fructose (high-fat high-carbohydrate diet [HFCD]) supplemented with Res and l-Car at doses of 25 and 300 mg/kg of body weight, respectively, for 63 d. An assessment of grip strength, behavioral reactions, as well as biochemical, morphological, and immunological parameters, was performed.

RESULTS

Res supplementation did not affect energy consumption, but l-Car increased when animals had free access to feed. Body weight gains were the highest in animals fed the HFCD, lowest in rats receiving the control balanced diet, and intermediate in animals receiving Res and l-Car. Feeding with Res and l-Car canceled the decrease in long-term memory in rats fed the HFCD, as well as reduced anxiety and increased mobility. With both supplements, bilirubin, triglycerides, and low-density lipoprotein levels in the blood plasma returned to normal values, but only l-Car increased the ratio of aspartic and alanine transaminases. In addition, l-Car lowered the levels of leptin and ghrelin and increased transforming growth factor beta 1 in the blood plasma, and consumption of Res was accompanied by a decrease in interleukin-17A and increase in interferon gamma in spleen lysates. Moreover, l-Car reduced the number of cells with lipid inclusions in the liver.

CONCLUSIONS

The consumption of Res and l-Car leads to a significant reduction in dyslipidemia and inflammation with potentially favorable changes in behavioral responses.

Microbial metabolite delta-valerobetaine is a diet-dependent obesogen

Obesity and obesity-related metabolic disorders are linked to the intestinal microbiome. However, the causality of changes in the microbiome-host interaction affecting energy metabolism remains controversial. Here, we show the microbiome-derived metabolite δ-valerobetaine (VB) is a diet-dependent obesogen that is increased with phenotypic obesity and is correlated with visceral adipose tissue mass in humans. VB is absent in germ-free mice and their mitochondria but present in ex-germ-free conventionalized mice and their mitochondria. Mechanistic studies in vivo and in vitro show VB is produced by diverse bacterial species and inhibits mitochondrial fatty acid oxidation through decreasing cellular carnitine and mitochondrial long-chain acyl-coenzyme As. VB administration to germ-free and conventional mice increases visceral fat mass and exacerbates hepatic steatosis with a western diet but not control diet. Thus, VB provides a molecular target to understand and potentially manage microbiome-host symbiosis or dysbiosis in diet-dependent obesity.

Preclinical Investigation of Alpinetin in the Treatment of Cancer-Induced Cachexia via Activating PPARγ

The ongoing loss of skeletal muscle is a central event of cancer cachexia, and its consequences include adverse effects on patient’s quality of life and survival. Alpinetin (Alp), a natural plant-derived flavonoid obtained from Alpinia katsumadai Hayata, has been reported to possess potent anti-inflammatory and antitumor activities. This study aimed to explore the therapeutic effect and underlying mechanism of Alp in the prevention of cancer cachexia. We found that Alp (25–100 μM) dose-dependently attenuated Lewis lung carcinoma–conditioned medium-induced C2C12 myotube atrophy and reduced expression of the E3 ligases Atrogin-1 and MuRF1. Moreover, Alp administration markedly improved vital features of cancer cachexia in vivo with visible reduction of the loss of tumor-free body weight and wasting of multiple tissues, including skeletal muscle, epididymal fat, and decreased expression of Atrogin-1 and MuRF1 in cachectic muscle. Alp suppressed the elevated spleen weight and serum concentrations of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6. Further, Alp treatment remained protective against cancer cachexia in the advanced stage of tumor growth. Molecular docking results suggested that Alp was docked into the active site of PPARγ with the docking score of –7.6 kcal/mol, forming a hydrogen bond interaction with PPARγ protein amino acid residue HIS449 with a bond length of 3.3 Å. Mechanism analysis revealed that Alp activated PPARγ, resulting in the downregulated phosphorylation of NF-κB and STAT3 in vitro and in vivo. PPARγ inhibition induced by GW9662 notably attenuated the improvement of Alp on the above cachexia phenomenon, indicating that PPARγ activation mediated the therapeutic effect of Alp. These findings suggested that Alp might be a potential therapeutic candidate against cancer cachexia.

Effect of l-carnitine on cardiotoxicity and apoptosis induced by imatinib through PDGF/ PPARγ /MAPK pathways

A tyrosine kinase inhibitor Imatinib (IM) is used in the treatment of different varieties of cancers. The current study was designed to explore the beneficial role of l-carnitine against IM-induced cardiotoxicity in rats. Male albino rats received IM (40 mg/kg, i.p.) either alone or/in combination with l-carnitine (100 mg/kg, i.p.) for 7 days. IM increased serum inflammatory cytokines, concomitant with activation of cardiac MAPK, α-SMA, malondialdehyde (MDA) and nitric oxide(NO), decreased cardiac peroxisome proliferator-activated receptor-γ (PPAR-γ) level, superoxide dismutase (SOD) activity, and glutathione (GSH) content. The expression levels of Bcl-2 and PDGF were significantly decreased, while the expression levels of CTGF and BAX were significantly increased in the IM group. The l-carnitine treatment successfully protected the heart as indicated by the improvement of the biochemical and histopathological parameters. l-carnitine didn't affect the serum concentration of IM and increased intracellular concentration in the combination-treated group as measured by the mass spectrometer. Conclusion: l-carnitine abrogated IM-induced cardiac damage and apoptosis via PDGF/PPARγ/MAPK pathways.

Inflammation-induced cholestasis in cancer cachexia

BACKGROUND

Cancer cachexia is a debilitating metabolic syndrome contributing to cancer death. Organs other than the muscle may contribute to the pathogenesis of cancer cachexia. This work explores new mechanisms underlying hepatic alterations in cancer cachexia.

METHODS

We used transcriptomics to reveal the hepatic gene expression profile in the colon carcinoma 26 cachectic mouse model. We performed bile acid, tissue mRNA, histological, biochemical, and western blot analyses. Two interventional studies were performed using a neutralizing interleukin 6 antibody and a bile acid sequestrant, cholestyramine. Our findings were evaluated in a cohort of 94 colorectal cancer patients with or without cachexia (43/51).

RESULTS

In colon carcinoma 26 cachectic mice, we discovered alterations in five inflammatory pathways as well as in other pathways, including bile acid metabolism, fatty acid metabolism, and xenobiotic metabolism (normalized enrichment scores of -1.97, -2.16, and -1.34, respectively; all Padj < 0.05). The hepatobiliary transport system was deeply impaired in cachectic mice, leading to increased systemic and hepatic bile acid levels (+1512 ± 511.6 pmol/mg, P = 0.01) and increased hepatic inflammatory cytokines and neutrophil recruitment to the liver of cachectic mice (+43.36 ± 16.01 neutrophils per square millimetre, P = 0.001). Adaptive mechanisms were set up to counteract this bile acid accumulation by repressing bile acid synthesis and by enhancing alternative routes of basolateral bile acid efflux. Targeting bile acids using cholestyramine reduced hepatic inflammation, without affecting the hepatobiliary transporters (e.g. tumour necrosis factor α signalling via NFκB and inflammatory response pathways, normalized enrichment scores of -1.44 and -1.36, all Padj < 0.05). Reducing interleukin 6 levels counteracted the change in expression of genes involved in the hepatobiliary transport, bile acid synthesis, and inflammation. Serum bile acid levels were increased in cachectic vs. non-cachectic cancer patients (e.g. total bile acids, +5.409 ± 1.834 μM, P = 0.026) and were strongly correlated to systemic inflammation (taurochenodeoxycholic acid and C-reactive protein: ρ = 0.36, Padj = 0.017).

CONCLUSIONS

We show alterations in bile acid metabolism and hepatobiliary secretion in cancer cachexia. In this context, we demonstrate the contribution of systemic inflammation to the impairment of the hepatobiliary transport system and the role played by bile acids in the hepatic inflammation. This work paves the way to a better understanding of the role of the liver in cancer cachexia.

Potential roles of mitochondrial cofactors in the adjuvant mitigation of proinflammatory acute infections, as in the case of sepsis and COVID-19 pneumonia

BACKGROUND

The mitochondrial cofactors α-lipoic acid (ALA), coenzyme Q10 (CoQ10) and carnitine (CARN) play distinct and complementary roles in mitochondrial functioning, along with strong antioxidant actions. Also termed mitochondrial nutrients (MNs), these cofactors have demonstrated specific protective actions in a number of chronic disorders, as assessed in a well-established body of literature.

METHODS

Using PubMed, the authors searched for articles containing information on the utilization of MNs in inflammatory disorders as assessed from in vitro and animal studies, and in clinical trials, in terms of exerting anti-inflammatory actions.

RESULTS

The retrieved literature provided evidence relating acute pathologic conditions, such as sepsis and pneumonia, with a number of redox endpoints of biological and clinical relevance. Among these findings, both ALA and CARN were effective in counteracting inflammation-associated redox biomarkers, while CoQ10 showed decreased levels in proinflammatory conditions. MN-associated antioxidant actions were applied in a number of acute disorders, mostly using one MN. The body of literature assessing the safety and the complementary roles of MNs taken together suggests an adjuvant role of MN combinations in counteracting oxidative stress in sepsis and other acute disorders, including COVID-19-associated pneumonia.

CONCLUSIONS

The present state of art in the use of individual MNs in acute disorders suggests planning adjuvant therapy trials utilizing MN combinations aimed at counteracting proinflammatory conditions, as in the case of pneumonia and the COVID-19 pandemic.

Phosphodiesterase Type 5 Inhibitors and Selective Estrogen Receptor Modulators Can Prevent But Not Reverse Myofibroblast Transformation in Peyronie's Disease

BACKGROUND

Myofibroblast transformation is a key step in the pathogenesis of Peyronie's disease (PD). Phosphodiesterase type 5 inhibitors (PDE5is) and selective estrogen receptor modulators (SERMs) can prevent the formation of fibrosis in in vitro and in vivo models of PD. However, it is unknown whether these drugs can also reverse established fibrosis.

AIM

To investigate whether PDE5is and SERMs can reverse transforming growth factor beta 1 (TGF-β1)-induced myofibroblast transformation and determine the point of no return.

METHODS

In-Cell enzyme-linked immunosorbent assay was used to quantify TGF-β1-induced myofibroblast transformation of human primary fibroblasts isolated from tunica albuginea (TA) of patients undergoing surgery for treatment of PD. Extracellular matrix production and collagen contraction assays were used as secondary assays. Reverse transcription-quantitative polymerase chain reaction and In-Cell enzyme-linked immunosorbent assay were used to measure drug target expression. PDE5i (vardenafil) and SERM (tamoxifen) were applied at various time points after TGF-β1.

OUTCOMES

Reversibility of myofibroblast transformation and drug target expression were investigated in a time-dependent manner in TA-derived fibroblasts.

RESULTS

Vardenafil or tamoxifen could not reverse the myofibroblast traits of alpha-smooth muscle actin expression and extracellular matrix production, whereas only tamoxifen affected collagen contraction after 72 hours of TGF-β1 treatment. Phosphodiesterase 5A and estrogen receptor (ER)-β were downregulated after 72 hours, and estrogen receptor -α protein could not be quantified. Tamoxifen could prevent myofibroblast transformation until 36 hours after TGF-β1 treatment, whereas vardenafil could prevent only 24 hours after TGF-β1 treatment. This was mirrored by downregulation of drug targets on mRNA and protein level. Furthermore, antifibrotic signaling pathways, peroxisome proliferator-activated receptor gamma and betaglycan (TGFB receptor III), were significantly downregulated after 36 hours of TGF-β1 exposure, as opposed to upregulation of profibrotic thrombospondin-1 at the same time point.

CLINICAL TRANSLATION

This study suggests that using PDE5is and SERMs might only help for early-phase PD and further highlights the need to test drugs at the appropriate stage of the disease based on their mechanism of action.

STRENGTHS & LIMITATIONS

The study uses primary human TA-derived fibroblasts that enhances translatability of the results. Limitations include that only 1 example of PDE5i- and SERM-type drug was tested. Time course experiments were only performed for marker expression experiments and not for functional assays.

CONCLUSION

This is the first study to demonstrate that timing for administration of drugs affecting myofibroblast transformation appears to be vital in in vitro models of PD, where 36 hours of TGF-β1 treatment can be suggested as a "point of no return" for myofibroblast transformation. Ilg MM, Stafford SJ, Mateus M, et al. Phosphodiesterase Type 5 Inhibitors and Selective Estrogen Receptor Modulators Can Prevent But Not Reverse Myofibroblast Transformation in Peyronie's Disease. J Sex Med 2020;17:1848-1864.

Potential use of C-phycocyanin in non-alcoholic fatty liver disease

C-phycocyanin (C-PC) is a kind of photosynthetically assisted pigment, which is ubiquitous in cyanobacteria cells. We investigated the effect of C-PC on non-alcoholic fatty liver disease (NAFLD) and its mechanism. Through oil red O staining, TC/TG detection, liver SOD/MDA detection and liver H&E staining, we found that C-PC could significantly reduce the lipid accumulation in the steatosis L02 cells and the liver of non-alcoholic steatohepatitis (NASH) mice, and improve the antioxidant capacity of liver. The results of Western Blotting showed that C-PC upregulated the expression of AMPK phosphorylation and downregulated SREBP-1c and its target genes ACC and FAS expression levels. Furthermore, C-PC also upregulated the expression of transcription factor PPARα, which was regulated by AMPK, and its target genes CPT1 level. In addition, C-PC could promote AMPK phosphorylation in hepatocytes while increasing the phosphorylation level of ACC in vivo and in vitro. Besides, C-PC could also improve the liver inflammatory infiltration by upregulated the expression of PPARγ and downregulated the expression of CD36, IL6 and TNFα. These results indicate that C-PC may improve hepatic lipid accumulation and inflammation in the non-alcoholic fatty liver mice by activating AMPK pathway of hepatocytes. The finding provides important help for the research and development of C-PC in the nutraceuticals and therapeutics of NAFLD.

Cancer Cachexia and Related Metabolic Dysfunction

Cancer cachexia is a complex multifactorial syndrome marked by a continuous depletion of skeletal muscle mass associated, in some cases, with a reduction in fat mass. It is irreversible by nutritional support alone and affects up to 74% of patients with cancer-dependent on the underlying type of cancer-and is associated with physical function impairment, reduced response to cancer-related therapy, and higher mortality. Organs, like muscle, adipose tissue, and liver, play an important role in the progression of cancer cachexia by exacerbating the pro- and anti-inflammatory response initially activated by the tumor and the immune system of the host. Moreover, this metabolic dysfunction is produced by alterations in glucose, lipids, and protein metabolism that, when maintained chronically, may lead to the loss of skeletal muscle and adipose tissue. Although a couple of drugs have yielded positive results in increasing lean body mass with limited impact on physical function, a single therapy has not lead to effective treatment of this condition. Therefore, a multimodal intervention, including pharmacological agents, nutritional support, and physical exercise, may be a reasonable approach for future studies to better understand and prevent the wasting of body compartments in patients with cancer cachexia.

L-carnitine supplementation attenuates NAFLD progression and cardiac dysfunction in a mouse model fed with methionine and choline-deficient diet

Non-alcoholic fatty liver disease (NAFLD) is a common cause of chronic liver disorder. NAFLD, associated lipotoxicity, fibrosis, oxidative stress, and altered mitochondrial metabolism, is responsible for systemic inflammation, which contributes to organ dysfunction in extrahepatic tissues, including the heart. We investigated the ability of L-carnitine (LC) to oppose the pathogenic mechanisms underlying NAFLD progression and associated heart dysfunction, in a mouse model of methionine-choline-deficient diet (MCDD). Mice were divided into three groups: namely, the control group (CONTR) fed with a regular diet and two groups fed with MCDD for 6 weeks. In the last 3 weeks, one of the MCDD groups received LC (200 mg/kg each day) through drinking water (MCDD + LC). The hepatic lipid accumulation and oxidative stress decreased after LC supplementation, which also reduced hepatic fibrosis via modulation of α-smooth muscle actin (αSMA), peroxisome-activated receptor gamma (PPARγ), and nuclear factor kappa B (NfƙB) expression. LC ameliorated systemic inflammation, mitigated cardiac reactive oxygen species (ROS) production, and prevented fibrosis progression by acting on signal transducer and activator of transcription 3 (STAT3), extracellular signal-regulated kinase 1-2 (ERK1-2), and αSMA. This study confirms the existence of a relationship between fatty liver disease and cardiac abnormalities and highlights the role of LC in controlling liver oxidative stress, steatosis, fibrosis, and NAFLD-associated cardiac dysfunction.

Fatty acid oxidation inhibitor etomoxir suppresses tumor progression and induces cell cycle arrest via PPARγ-mediated pathway in bladder cancer

Tumor cells rely on aerobic glycolysis as their main energy resource (Warburg effect). Recent research has highlighted the importance of lipid metabolism in tumor progression, and certain cancers even turn to fatty acids as the main fuel. Related studies have identified alterations of fatty acid metabolism in human bladder cancer (BCa). Our microarray analysis showed that fatty acid metabolism was activated in BCa compared with normal bladder. The free fatty acid (FFA) level was also increased in BCa compared with paracancerous tissues. Inhibition of fatty acid oxidation (FAO) with etomoxir caused lipid accumulation, decreased adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH) levels, suppressed BCa cell growth in vitro and in vivo, and reduced motility of BCa cells via affecting epithelial-mesenchymal transition (EMT)-related proteins. Furthermore, etomoxir induced BCa cell cycle arrest at G₀/G₁ phase through peroxisome proliferator-activated receptor (PPAR) γ-mediated pathway with alterations in fatty acid metabolism associated gene expression. The cell cycle arrest could be reversed by PPARγ antagonist GW9662. Taken together, our results suggest that inhibition of FAO with etomoxir may provide a novel avenue to investigate new therapeutic approaches to human BCa.

Inflammatory mechanisms and oxidative stress in prostatitis: the possible role of antioxidant therapy

This article focuses on the role that oxidative stress plays in chronic prostatitis, not only with respect to the known impact on symptoms and fertility but also especially in relation to possible prostate cancer development. Prostatitis is the most common urologic disease in adult males younger than 50 years and the third most common urologic diagnosis in males older than 50 years. If the germ-causing acute prostatitis is not eliminated, the inflammatory process becomes chronic. Persistent inflammation causes ongoing production of large quantities of pro-inflammatory cytokines and both oxygen and nitrogen reactive species, with consequent activation of transcription factor nuclear factor-kappa B (NF-κB) and genes encoding for further production of pro-inflammatory cytokines, chemotactic factors, and growth factors. Confirming the role of oxidative stress in chronic prostatitis, several studies have demonstrated the presence of oxidative stress markers in the genital secretions of patients suffering from the disease. Antioxidants can therefore play an essential role in the treatment of chronic bacterial and non-bacterial prostatitis; in the case of bacterial inflammation, they can be associated with antibiotic therapy. Moreover, due to their anti-inflammatory properties, antioxidants hinder the progression of inflammation and the possible development of prostate cancer.

l-Carnitine Supplementation in Older Women. A Pilot Study on Aging Skeletal Muscle Mass and Function

Skeletal muscle wasting, associated with aging, may be regulated by the inflammatory cytokines as well as by insulin-like growth factor 1 (IGF-1). l-carnitine possesses anti-inflammatory properties and increases plasma IGF-1 concentration, leading to the regulation of the genes responsible for protein catabolism and anabolism. The purpose of the present study was to evaluate the effect of a 24-week l-carnitine supplementation on serum inflammatory markers, IGF-1, body composition and skeletal muscle strength in healthy human subjects over 65 years of age. Women between 65 and 70 years of age were supplemented for 24 weeks with either 1500 mg l-carnitine-l-tartrate or an isonitrogenous placebo per day in a double-blind fashion. Before and after the supplementation protocol, body mass and composition, as well as knee extensor and flexor muscle strength were determined. In the blood samples, free carnitine, interleukin-6, tumor necrosis factor-α, C-reactive protein and IGF-1 were determined. A marked increase in free plasma carnitine concentration was observed due to l-carnitine supplementation. No substantial changes in other parameters were noted. In the current study, supplementation for 24 weeks affected neither the skeletal muscle strength nor circulating markers in healthy women over 65 years of age. Positive and negative aspects of l-carnitine supplementation need to be clarified.

Recent Pathophysiological Aspects of Peyronie's Disease: Role of Free Radicals, Rationale, and Therapeutic Implications for Antioxidant Treatment-Literature Review

Peyronie's disease (PD) is a chronic inflammation of tunica albuginea of the corpora cavernosa that causes an inelastic plaque resulting in penis deformation. Although its etiology is not completely known, there is general consensus that PD is genetically transmitted and secondary to penile trauma. In recent years, numerous studies demonstrated the role played by oxidative stress in PD pathogenesis, and other studies have described successful use of antioxidants in PD treatment. Oxidative stress is an integral part of this disease, influencing its progression. In the early stages of PD, the inflammatory infiltrate cells produce high quantities of free radicals and proinflammatory and profibrotic cytokines, with consequent activation of transcription factor NF-κB. While conservative therapies commonly used in the early stages of PD include oral substances (Potaba, tamoxifen, colchicine, and vitamin E), intralesional treatment (verapamil, interferon, steroids, and more recently collagenase clostridium histolyticum-Xiaflex), and local physical treatment (iontophoresis, extracorporeal shock wave therapy, and penile extender), the significant results obtained by emerging treatments with the antioxidants cited in this article suggest these therapeutic agents interfere at several levels with the disease's pathogenetic mechanisms. Antioxidants therapy outcomes are interesting for good clinical practice and also confirm the fundamental role played by oxidative stress in PD.