The Effects of Melatonin on Elevated Liver Enzymes during Statin Treatment

Therapeutic applications of melatonin in disorders related to the gastrointestinal tract and control of appetite

Most animals have large amounts of the special substance melatonin, which is controlled by the light/dark cycle in the suprachiasmatic nucleus. According to what is now understood, the gastrointestinal tract (GIT) and other areas of the body are sites of melatonin production. According to recent studies, the GIT and adjacent organs depend critically on a massive amount of melatonin. Not unexpectedly, melatonin's many biological properties, such as its antioxidant, anti-inflammatory, pro-apoptotic, anti-proliferative, anti-metastasis, and antiangiogenic properties, have drawn the attention of researchers more and more. Because melatonin is an antioxidant, it produces a lot of secretions in the GIT's mucus and saliva, which shields cells from damage and promotes the development of certain GIT-related disorders. Melatonin's ability to alter cellular behavior in the GIT and other associated organs, such as the liver and pancreas, is another way that it functions. This behavior alters the secretory and metabolic activities of these cells. In this review, we attempted to shed fresh light on the many roles that melatonin plays in the various regions of the gastrointestinal tract by focusing on its activities for the first time.

Methadone administered to rat dams during pregnancy and lactation affects the circadian rhythms of their pups

The circadian clock is one of the most important homeostatic systems regulating the majority of physiological functions. Its proper development contributes significantly to the maintenance of health in adulthood. Methadone is recommended for the treatment of opioid use disorders during pregnancy, increasing the number of children prenatally exposed to long-acting opioids. Although early-life opioid exposure has been studied for a number of behavioral and physiological changes observed later in life, information on the relationship between the effects of methadone exposure and circadian system development is lacking. Using a rat model, we investigated the effects of prenatal and early postnatal methadone administration on the maturation of the circadian clockwork in the suprachiasmatic nucleus (SCN) and liver, the rhythm of aralkylamine N-acetyltransferase (AA-NAT) activity in the pineal gland, and gene expression in the livers of 20-day-old rats. Our data show that repeated administration of methadone to pregnant and lactating mothers has significant effect on rhythmic gene expression in the SCN and livers and on the rhythm of AA-NAT in the offspring. Similar to previous studies with morphine, the rhythm amplitudes of the clock genes in the SCN and liver were unchanged or enhanced. However, six of seven specific genes in the liver showed significant downregulation of their expression, compared to the controls in at least one experimental group. Importantly, the amplitude of the AA-NAT rhythm was significantly reduced in all methadone-treated groups. As there is a strong correlation with melatonin levels, this result could be of importance for clinical practice.

Hepatic Encephalopathy and Melatonin

Hepatic encephalopathy (HE) is a severe metabolic syndrome linked with acute/chronic hepatic disorders. HE is also a pernicious neuropsychiatric complication associated with cognitive decline, coma, and death. Limited therapies are available to treat HE, which is formidable to oversee in the clinic. Thus, determining a novel therapeutic approach is essential. The pathogenesis of HE has not been well established. According to various scientific reports, neuropathological symptoms arise due to excessive accumulation of ammonia, which is transported to the brain via the blood–brain barrier (BBB), triggering oxidative stress and inflammation, and disturbing neuronal-glial functions. The treatment of HE involves eliminating hyperammonemia by enhancing the ammonia scavenging mechanism in systemic blood circulation. Melatonin is the sole endogenous hormone linked with HE. Melatonin as a neurohormone is a potent antioxidant that is primarily synthesized and released by the brain’s pineal gland. Several HE and liver cirrhosis clinical studies have demonstrated impaired synthesis, secretion of melatonin, and circadian patterns. Melatonin can cross the BBB and is involved in various neuroprotective actions on the HE brain. Hence, we aim to elucidate how HE impairs brain functions, and elucidate the precise molecular mechanism of melatonin that reverses the HE effects on the central nervous system.

Safety of higher doses of melatonin in adults: A systematic review and meta-analysis

Melatonin is commonly used for sleep and jetlag at low doses. However, there is less documentation on the safety of higher doses, which are being increasingly used for a wide variety of conditions, including more recently COVID-19 prevention and treatment. The aim of this review was to investigate the safety of higher doses of melatonin in adults. Medline, Scopus, Embase and PsycINFO databases from inception until December 2019 with convenience searches until October 2020. Randomised controlled trials investigating high-dose melatonin (≥10 mg) in human adults over 30 years of age were included. Two investigators independently abstracted articles using PRISMA guidelines. Risk of bias was assessed by a committee of three investigators. 79 studies were identified with a total of 3861 participants. Studies included a large range of medical conditions. The meta-analysis was pooled data using a random effects model. The outcomes examined were the number of adverse events (AEs), serious adverse events (SAEs) and withdrawals due to AEs. A total of 29 studies (37%) made no mention of the presence or absence of AEs. Overall, only four studies met the pre-specified low risk of bias criteria for meta-analysis. In that small subset, melatonin did not cause a detectable increase in SAEs (Rate Ratio = 0.88 [0.52, 1.50], p = .64) or withdrawals due to AEs (0.93 [0.24, 3.56], p = .92), but did appear to increase the risk of AEs such as drowsiness, headache and dizziness (1.40 [1.15, 1.69], p < .001). Overall, there has been limited AE reporting from high-dose melatonin studies. Based on this limited evidence, melatonin appears to have a good safety profile. Better safety reporting in future long-term trials is needed to confirm this as our confidence limits were very wide due to the paucity of suitable data.

Melatonin Levels in Patients with Nonalcoholic Fatty Liver Disease Compared with Healthy Individuals according to Fibrosis Level

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is one of the most common diseases worldwide. Studies have shown that melatonin, as a regulatory hormone, is effective in different cell protective pathways. We aimed to compare serum melatonin levels of patients with NAFLD with different stages of fibrosis with that of healthy individuals.

METHODS

In this cross-sectional study patients, aged >20 years with elevated serum liver enzymes and trance abdominal sonographic diagnosis of fatty liver who met the exclusion criteria for NAFLD were included. The participants were categorized into three groups as follows: 1) severe fibrosis (fibrosis > 9.1 kPa and steatosis > 285 dbm), 2) mild-moderate fibrosis (fibrosis: 6-9.0 kPa and steatosis 240-285), and 3) normal group with fibrosis < 5.8 kPa and steatosis < 240 dbm based on Fibroscan evaluation. Five ml of fasting venous blood was taken from each patient and the control group for laboratory assessment. A questionnaire including demographic, anthropometric, laboratories (serum ALT, AST, triglyceride, total cholesterol and melatonin level), and clinical data was completed for all participants.

RESULTS

97 people with a mean±SD age of 42.21 ± 11 years were enrolled. 59 (60.0%) patients were women. we observed that the melatonin levels were increased by advancing fibrosis. Based on control- attenuated parameter results the melatonin levels significantly differed between the healthy individuals and patients with severe steatosis. There was a direct association between increased melatonin levels and liver enzymes.

CONCLUSION

As a regulatory hormone, melatonin may directly be associated with liver cell injuries. Therefore, considered regulatory substances such as melatonin either diagnostic or therapeutic can improve the patients’ outcome.

Oleic acid-reinforced PEGylated polymethacrylate transdermal film with enhanced antidyslipidemic activity and bioavailability of atorvastatin: A mechanistic ex-vivo/in-vivo analysis

To enhance the poor bioavailability and extensive liver metabolism of atorvastatin calcium (ATC), we have developed an oleic acid-reinforced PEGylated polymethacrylate (OLA-PEG-E-RLPO) transdermal film as a convenient and alternative delivery system. The effect of varying levels of Eudragit RLPO, PEG 400, and oleic acid on the target product profile was optimized through Quality by Design (QbD) approach. The ATC-loaded OLA-PEG-E-RLPO transdermal films were evaluated in ex-vivo experiments using full thickness skin, utilizing Franz cell studies, and undergone in-vivo pharmacokinetics/pharmacodynamics (PK/PD) assessment, using poloxamer-induced dyslipidemic Sprague-Dawley rats. At 2 and 12 h, the optimized ATC films with a thickness of 0.79 mm showed permeation of 37.34% and 97.23% into the receptor compartment, respectively. Steady-state flux was 0.172 mg/cm²h, with 7.01 × 10^-4 cm/h permeability coefficient, and 0.713 × 10^-3 cm²/h diffusion coefficient. In-vivo PK results indicated that the absorption profiles (AUC_0-∞) of the optimized film in pre-treated group of animals were 8.6-fold and 2.8-fold greater than controls pre-treated with non-PEGylated non-oleic acid film and orally administered ATC, respectively. PD assessment of the lipid panel indicated that the lipid profile of the optimized film pre-treated group reached normal levels after 12 h, along with the significant enhancement over the non-PEGylated non-oleic acid film and the oral marketed tablet groups. The histopathological findings revealed near-normal hepatocyte structure for the optimized film pre-treated animal group. Our results further indicate that transdermal delivery films based on an optimized ATC-loaded OLA-PEG-E-RLPO were successfully developed and their assessment in both ex-vivo and in-vivo suggests enhanced permeability and improvement in bioavailability and antidyslipidemic activity of ATC. This approach can provide several advantages, especially during chronic administration of ATC, including improvement in patient compliance, therapeutic benefits, bioavailability, and feasibility for commercialization and as a platform for other drug classes.

A double-blind, randomized, placebo-controlled pilot trial of atorvastatin for nephrogenic diabetes insipidus in lithium users

OBJECTIVE

Lithium remains an important treatment for mood disorders but is associated with kidney disease. Nephrogenic diabetes insipidus (NDI) is associated with up to 3-fold risk of incident chronic kidney disease among lithium users. There are limited randomized controlled trials (RCT) for treatments of lithium-induced NDI, and existing therapies can be poorly tolerated. Therefore, novel treatments are needed for lithium-induced NDI.

METHOD

We conducted a 12-week double-blind pilot RCT to assess the feasibility and efficacy of 20 mg/d atorvastatin vs placebo in the treatment of NDI in chronic lithium users. Patients, recruited between September 2017 and October 2018, were aged 18 to 85, currently on a stable dose of lithium, and determined to have NDI.

RESULTS

Urinary osmolality (UOsm) at 12 weeks adjusted for baseline was not statistically different between groups (+39.6 mOsm/kg [95% CI, -35.3, 114.5] in atorvastatin compared to placebo groups). Secondary outcomes of fluid intake and aquaporin-2 excretions at 12 weeks adjusted for baseline were -0.13 L [95% CI, -0.54, 0.28] and 98.68 [95% CI, -190.34, 387.70], respectively. A moderate effect size was observed for improvements in baseline UOsm by ≥100 mOsm/kg at 12 weeks in patients who received atorvastatin compared to placebo (38.45% (10/26) vs 22.58% (7/31); Cohen's d = 0.66).

CONCLUSION

Among lithium users with NDI, atorvastatin 20 mg/d did not significantly improve urinary osmolality compared to placebo over a 12-week period. Larger confirmatory trials with longer follow-up periods may help to further assess the effects of statins on NDI, especially within patients with more severe NDI.

A Pilot Randomized, Clinical Trial of the Anti-pruritus Effect of Melatonin in Patients with Chronic Liver Disease

Pruritus is one of the disturbing complications induced by chronic liver disease (CLD), bearing a negative impact on patient quality of life and potentially resulting in early liver transplants. Given the main role of the autotaxin enzyme in pruritus induced by CLD and the suppressive effects of melatonin on the expression of the autotaxin gene, this study was designed to evaluate the antipruritic effect of melatonin in patients with CLD. A double-blind, cross-over, randomized, placebo-controlled pilot trial was conducted on patients with CLD -induced pruritis. Patients were randomly assigned to two groups where they received melatonin 10-mg at night or placebo for 2 weeks. After a 2-week washout period, patients were then crossed over to the other group. The Visual Analog Scale (VAS) and the 12-Item Pruritus Severity Score (12-PSS) were used to assess patient response to therapy as the co-primary outcomes, while liver function tests were assayed too. Forty patients completed the study. The VAS score showed alleviation of 3.21 ± 2.24 (in pruritus) with melatonin (p-value <0.05). The study goal (a reduction of at least 20% in VAS) was achieved in 33 (82%) of study participants. In patients who received melatonin, the 12-PSS and Body Surface Area (BSA) affected by pruritus decreased on average 46.57% and 51.71%, respectively, with mood, sleep pattern and daily activity levels also demonstrating significant improvement (p-value < 0.05). Melatonin was found to be effective for managing pruritus in patients with CLD.

Melatonin effect on platelet count in patients with liver disease

AIM

A positive effect of melatonin on platelet count in patients with chronic liver disease is reported in the current study.

BACKGROUND

Thrombocytopenia occurs when the severity of liver disease is exacerbated. Reduction in the secretion of thrombopoetin, as an intrinsic hormone produced mainly by the liver, plays an important role in this complication induced by liver disease.

METHODS

This research was a double-blind, cross-over, placebo-controlled pilot study. Patients with liver disease were given two 5-mg pearls of melatonin or a placebo for two weeks, and after a 2-week washout period, their groups were switched. Liver function tests and platelet counts were assessed once at the beginning and once at the end of each phase of the study.

RESULTS

In the current study, 40 patients meeting the eligibility criteria were included. The average platelet count was significantly increased by melatonin in comparison with the placebo (from 175.67±92.84 to 191.10±98.82 vs. from 185.22±98.39 to 176.45±91.45) (p-value <0.001). Melatonin also significantly reduced ALT, AST, total bilirubin, and direct and MELD scores in patients with liver disease (p-value <0.05).

CONCLUSION

Melatonin may increase platelet count and inhibit thrombocytopenia in patients with liver disease; however, more investigations are needed to confirm the current results.

Managing hyperlipidaemia in patients with COVID-19 and during its pandemic: An expert panel position statement from HEART UK

The emergence of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which causes Coronavirus Disease 2019 (COVID-19) has resulted in a pandemic. SARS-CoV-2 is highly contagious and its severity highly variable. The fatality rate is unpredictable but is amplified by several factors including advancing age, atherosclerotic cardiovascular disease, diabetes mellitus, hypertension and obesity. A large proportion of patients with these conditions are treated with lipid lowering medication and questions regarding the safety of continuing lipid-lowering medication in patients infected with COVID-19 have arisen. Some have suggested they may exacerbate their condition. It is important to consider known interactions with lipid-lowering agents and with specific therapies for COVID-19. This statement aims to collate current evidence surrounding the safety of lipid-lowering medications in patients who have COVID-19. We offer a consensus view based on current knowledge and we rated the strength and level of evidence for these recommendations. Pubmed, Google scholar and Web of Science were searched extensively for articles using search terms: SARS-CoV-2, COVID-19, coronavirus, Lipids, Statin, Fibrates, Ezetimibe, PCSK9 monoclonal antibodies, nicotinic acid, bile acid sequestrants, nutraceuticals, red yeast rice, Omega-3-Fatty acids, Lomitapide, hypercholesterolaemia, dyslipidaemia and Volanesorsen. There is no evidence currently that lipid lowering therapy is unsafe in patients with COVID-19 infection. Lipid-lowering therapy should not be interrupted because of the pandemic or in patients at increased risk of COVID-19 infection. In patients with confirmed COVID-19, care should be taken to avoid drug interactions, between lipid-lowering medications and drugs that may be used to treat COVID-19, especially in patients with abnormalities in liver function tests.

The Protective Effects of Melatonin on Aluminum-Induced Hepatotoxicity and Nephrotoxicity in Rats

Aluminum (Al) is a ubiquitous element with known toxicity for both humans and animals. Herein, we aimed to investigate the potential role of melatonin (MEL) in hepatotoxicity and nephrotoxicity following aluminum chloride (AlCl₃) treatment in rats. Adult male rats were treated with AlCl₃ (34 mg/kg bwt) for eight weeks. Exposure to AlCl₃ enhanced the serum activities of the liver transaminases (alanine aminotransferase and aspartate aminotransferase) and increased the level of bilirubin, in addition to the serum kidney function markers urea and creatinine. AlCl₃ intoxication boosted oxidative stress, as evidenced by increases in the levels of lipid peroxidation (LPO) and nitric oxide (NO) along with simultaneous decreases in the levels of glutathione (GSH), various antioxidant enzymes, and Nrf2 mRNA expression. MEL (5 mg/kg bwt) treatment repressed LPO and NO levels, whereas it augmented GSH content. The activities of the antioxidant enzymes GPx, SOD, CAT, and GR were also restored concomitantly when MEL was administered before AlCl₃. MEL also suppressed the apoptotic effect of AlCl₃ by enhancing Bcl-2 protein expression in the liver and kidney and decreasing the expression levels of proinflammatory cytokines. Histopathological findings in the liver and kidney tissues confirmed the beneficial effect of MEL against AlCl₃ toxicity. These findings indicate that MEL prevents AlCl₃ toxicity by enhancing the antioxidant defense system.

Boosting transdermal delivery of atorvastatin calcium via o/w nanoemulsifying system: Two-step optimization, ex vivo and in vivo evaluation

A nanoemulsion system was designed for Atorvastatin calcium (ATOR) transdermal delivery to overcome its poor bioavailability of (30%) resulting from the extensive first-pass effect and dissolution rate-limited in vivo absorption. Pseudo ternary phase diagrams were developed, and various NE formulae were prepared using oleic acid (OA), Tween 80 as surfactant and PEG 400 as cosurfactant, ethanol and limonene as permeation enhancers (PEs). NEs were characterized for morphology, droplet size, zeta potential and in vitro release. The optimized formulae were assessed for ex vivo transdermal permeation and in vivo pharmacodynamic/pharmacokinetic studies. Hypocholesterolemic effect after 7 days skin treatment was detected and compared to oral ATOR dispersion. Finally, blood plasma levels were measured for 24 h for rats received the selected transdermal NE and transdermal drug in OA. The obtained results suggested the low potentiality of NE systems in transdermal delivery of lipophilic drugs, only the addition of PEs is driving factor for increasing drug flux through full thickness rat skin. In the optimized formula, the presence of ethanol and PEG 400 disrupts SC lipids exhibiting rapid ex vivo release profile compared to other NEs and to ATOR in OA. In contrast, the optimized NE achieved a prolonged plasma profile. Transdermal NE was significantly more efficient than oral administration in lowering cholesterol plasma level and in increasing ATOR bioavailability. In conclusion, data revealed no correlation between ex vivo and in vivo studies explained by the collapse of the follicles in ex vivo skin permeation study, leaving only the lipoidal pathway for NE to pass through, thus only NE components, neither nanosizing nor other reported mechanisms, are the main influencing factors. In vivo experiments suggested that o/w NE changed ATOR pathway to follicular delivery leading to accumulation of NE in follicles and consequently a prolonged plasma profile.

Possible application of melatonin treatment in human diseases of the biliary tract

Melatonin was discovered in 1958 by Aaron Lerner. Its name comes from the ability of melatonin to change the shape of amphibian melanophores from stellate to roundish. Starting from the 1980s, the role of melatonin in the regulation of mammalian circadian and seasonal clocks has been elucidated. Presently, several other effects have been identified in different organs. For example, the beneficial effects of melatonin in models of liver damage have been described. This review gives first a general background on experimental and clinical data on the use of melatonin in liver damage. The second part of the review focuses on the findings related to the role of melatonin in biliary functions, suggesting a possible use of melatonin therapy in human diseases of the biliary tree.

Melatonin modulates inflammatory mediators and improves olanzapine-induced hepatic steatosis in rat model of schizophrenia

BACKGROUND

Melatonin (Mel) has lower levels and can be used as monotherapy in schizophrenia. Mel alleviated liver steatosis induced by atypical antipsychotics.

GOALS

To investigate Mel effect as monotherapy and addon treatment on ketamine-induced behavioral changes in rat schizophrenia model and olanzapine (Ola)-induced metabolic derangement.

METHODS

24 male rats divided into four groups; C: control; O: Ola; OM: Ola plus Mel and M: Mel. All groups treated orally daily for 25 days. We measured activities of daily life (ADL) and rat performance in radial arm water maze (RAWM) before and after ketamine (Ket) injection, serum level of liver enzymes, lipoproteins, sugar, inflammatory markers and liver histopathology.

RESULTS

Ket significantly reduced burrowing and hoarding behavior, increased working memory errors (WME) and time to reach target (TRT). Ola antagonized the deleterious effects of Ket on ADL, WME and TRT. Mel monotherapy significantly reduced burrowing and doesn't affect hoarding, WME or TRT in RAWM. Significant rise in ALT, AST, IL-1 beta, IL-6, IL-10, TNF-alpha, LDL, TGs and hepatic steatosis score (HSS) in O compared to C group. Co administration of Mel significantly decreased ALT, AST, IL-1 beta, IL-6 and TNF alpha. Insignificant difference in IL-10, TGs or LDL and significant improvement in HSS in OM compared to O group. Insignificant change in HDL or blood sugar in both O and OM groups compared to C group detected.

CONCLUSION

Although ineffective as monotherapy, Mel co administration provides promising natural way to improve Ola-induced hepatic derangement in psychotic disorders.

Is melatonin effective for pruritus caused by liver disease?

There is still no definitive treatment to relieve pruritus associated with liver disease, because the precise mechanism of itching has not yet been determined. Different mechanisms have been proposed. One recent explanation is thought to be the rise in serum levels of lysophosphatidic acid which is a metabolite of lysophosphatidyl choline conversion by autotaxin enzyme in liver disease is. Over expression of autotaxin which occurs in atopic dermatitis has been shown to be involved in itching pathology. Importantly, gene amplification of autotaxin also occurs in cholestasis. Melatonin has pleiotropic properties such as suppressive effects on serum level of autotaxin which relieves itching of atopic dermatitis. Due to some similarities in mechanism of itching, it is hypothesized that melatonin may improve itching of liver diseases.

Adverse events associated with oral administration of melatonin: A critical systematic review of clinical evidence

While melatonin was once thought of simply as a sleep-inducing hormone, recent research has resulted in development of a deeper understanding of the complex physiological activity of melatonin in the human body. Along with this understanding has come widespread, increasing use of melatonin supplementation, extending beyond its traditional use as a sleep aid into novel fields of application. This increased use often involves off-label and self-prescription, escalating the importance of safety data. In order to examine the current knowledge relating to safety of the exogenous neurohormone, we conducted a comprehensive, critical systematic review of clinical evidence. We examined controlled studies of oral melatonin supplementation in humans when they presented any statistical analysis of adverse events. Of the fifty articles identified, twenty-six found no statistically significant adverse events, while twenty-four articles reported on at least one statistically significant adverse event. Adverse events were generally minor, short-lived and easily managed, with the most commonly reported adverse events relating to fatigue, mood, or psychomotor and neurocognitive performance. A few studies noted adverse events relating to endocrine (e.g. reproductive parameters, glucose metabolism) and cardiovascular (e.g. blood pressure, heart rate) function, which appear to be influenced by dosage, dose timing and potential interactions with antihypertensive drugs. Oral melatonin supplementation in humans has a generally favourable safety profile with some exceptions. Most adverse effects can likely be easily avoided or managed by dosing in accordance with natural circadian rhythms. Further research is required to explore the potential for melatonin to interact with endogenous hormones and pharmaceuticals.