Vitamin D nanoemulsion enhances hepatoprotective effect of conventional vitamin D in rats fed with a high-fat diet

1,25-dihydroxyvitamin D3 improves non-alcoholic steatohepatitis phenotype in a diet-induced rat model

We studied the potential protective effects of 1,25-dihydroxyvitamin D3 (1,25 VD3) supplementation on liver damage induced by a choline-deficient (CD) diet in rats, where impaired liver function leads to decreased 25-hydroxyvitamin D3 levels, the precursor for the active 1,25 VD3. The CD diet reduced serum 25 VD3 levels and increased liver enzymes, indicative of liver damage. Conversely, 1,25 VD3 supplementation alleviated liver damage, reducing liver enzymes and improving histopathological features characteristic of non-alcoholic steatohepatitis (NASH). Oxidative stress and inflammation were mitigated by 1,25 VD3, as evidenced by decreased malondialdehyde and nuclear factor kappa B (NF-κB) expression, and increased total antioxidant capacity (TAOC). 1,25 VD3 also enhanced fatty acid metabolism by increasing peroxisome proliferator-activated receptor alpha (PPARα) and carnitine palmitoyltransferase-1 (CPT-1) expression, promoting lipid transport and oxidation. Additionally, 1,25 VD3 supplementation modulated inflammation by increasing PPARγ expression, reducing NF-κB expression, and decreasing pro-inflammatory cytokines (TNF-α, IL-1β). Anti-inflammatory cytokines (IL-10, IL-4) were increased, and macrophage polarization was shifted towards an anti-inflammatory M2 phenotype. Moreover, 1,25 VD3 upregulated CYP2J3, a cytochrome P450 epoxygenase that converts arachidonic acid to anti-inflammatory epoxyeicosatrienoic acids (EETs) and decreased soluble epoxide hydrolase activity, likely contributing to increased EET levels. Correlation studies revealed positive associations between 1,25 VD3 supplementation, CYP2J3 expression, EETs, as well as negative correlations with NF-κB and TNF-α. PPARα expression positively correlated with TAOC and CPT-1, while PPARγ expression negatively correlated with inflammatory markers. These findings demonstrate the therapeutic potential of 1,25 VD3 in alleviating NASH through regulation of fatty acid metabolism, inflammation, and oxidative stress.

AdipoRon, an adiponectin receptor agonist, modulates AMPK signaling pathway and alleviates ovalbumin-induced airway inflammation in a murine model of asthma

Asthma is a long-term disease that causes airways swelling and inflammation and in turn airway narrowing. AdipoRonis an orally active synthetic small molecule that acts as a selective agonist at theadiponectin receptor 1 and 2. The aim of the current study is to delineate the protective effect and the potential underlying mechanism ofadipoRon inairway inflammationinduced byovalbumin (OVA) in comparison withdexamethasone. Adult maleSwiss Albino micewere sensitized to OVA on days 0 and 7, then challenged with OVA on days 14, 15 and 16. AdipoRon was administered orally for 6 days starting from the 11th day till the 16th and 1 h prior to OVA in the challenge days. Obtained results from asthmatic control group showed a significant decrease in serum adiponectin concentration, an increase in inflammatory cell counts inthe bronchoalveolar lavage fluid(BALF), CD68 protein expression, inflammatory cytokine concentration and oxidative stress as well. Administration of adipoRon enhanced antioxidant mechanisms limiting oxidative stress by significantly increasing reduced glutathione (GSH) pulmonary content, decreasing serum lactate dehydrogenase (LDH) together with malondialdehyde (MDA) significant reduction in lung tissue. In addition, it modulated the levels of serum immunoglobulin E (IgE), pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-13, nuclear factor kappa B (NF-κB) and the anti-inflammatory one IL-10 improving lung inflammation as revealed by histopathological evaluation. Furthermore, lung tissue expression of nuclear factor erythroid 2-related factor (Nrf2) and 5'AMP-activated protein kinase (AMPK) were significantly increased adipoRon. Notably, results of adipoRon received group were comparable to those of dexamethasone group. In conclusion, our study demonstrates that adipoRon can positively modulate adiponectin expression with activation of AMPK pathway and subsequent improvement in inflammatory and oxidative signaling.

Oxidative Stress as a Target for Non-Pharmacological Intervention in MAFLD: Could There Be a Role for EVOO?

Oxidative stress plays a central role in most chronic liver diseases and, in particular, in metabolic dysfunction-associated fatty liver disease (MAFLD), the new definition of an old condition known as non-alcoholic fatty liver disease (NAFLD). The mechanisms leading to hepatocellular fat accumulation in genetically predisposed individuals who adopt a sedentary lifestyle and consume an obesogenic diet progress through mitochondrial and endoplasmic reticulum dysfunction, which amplifies reactive oxygen species (ROS) production, lipid peroxidation, malondialdehyde (MDA) formation, and influence the release of chronic inflammation and liver damage biomarkers, such as pro-inflammatory cytokines. This close pathogenetic link has been a key stimulus in the search for therapeutic approaches targeting oxidative stress to treat steatosis, and a number of clinical trials have been conducted to date on subjects with NAFLD using drugs as well as supplements or nutraceutical products. Vitamin E, Vitamin D, and Silybin are the most studied substances, but several non-pharmacological approaches have also been explored, especially lifestyle and diet modifications. Among the dietary approaches, the Mediterranean Diet (MD) seems to be the most reliable for affecting liver steatosis, probably with the added value of the presence of extra virgin olive oil (EVOO), a healthy food with a high content of monounsaturated fatty acids, especially oleic acid, and variable concentrations of phenols (oleocanthal) and phenolic alcohols, such as hydroxytyrosol (HT) and tyrosol (Tyr). In this review, we focus on non-pharmacological interventions in MAFLD treatment that target oxidative stress and, in particular, on the role of EVOO as one of the main antioxidant components of the MD.

VDR regulates mitochondrial function as a protective mechanism against renal tubular cell injury in diabetic rats

PURPOSE

To investigate the regulatory effect and mechanism of Vitamin D receptor (VDR) on mitochondrial function in renal tubular epithelial cell under diabetic status.

METHODS

The diabetic rats induced by streptozotocin (STZ) and HK-2 cells under high glocose(HG)/transforming growth factor beta (TGF-β) stimulation were used in this study. Calcitriol was administered for 24 weeks. Renal tubulointerstitial injury and some parameters of mitochondrial function including mitophagy, mitochondrial fission, mitochondrial ROS, mitochondrial membrane potential (MMP), mitochondrial ATP, Complex V activity and mitochondria-associated ER membranes (MAMs) integrity were examined. Additionally, paricalcitol, 3-MA (an autophagy inhibitor), VDR over-expression plasmid, VDR siRNA and Mfn2 siRNA were applied in vitro.

RESULTS

The expression of VDR, Pink1, Parkin, Fundc1, LC3II, Atg5, Mfn2, Mfn1 in renal tubular cell of diabetic rats were decreased significantly. Calcitriol treatment reduced the levels of urinary albumin, serum creatinine and attenuated renal tubulointerstitial fibrosis in STZ induced diabetic rats. In addition, VDR agonist relieved mitophagy dysfunction, MAMs integrity, and inhibited mitochondrial fission, mitochondrial ROS. Co-immunoprecipitation analysis demonstrated that VDR interacted directly with Mfn2. Mitochondrial function including mitophagy, mitochondrial membrane potential (MMP), mitochondrial Ca2+, mitochondrial ATP and Complex V activity were decreased dramatically in HK-2 cells under HG/TGF-β ambience. In vitro pretreatment of HK-2 cells with autophagy inhibitor 3-MA, VDR siRNA or Mfn2 siRNA negated the activating effects of paricalcitol on mitochondrial function. Pricalcitol and VDR over-expression plasmid activated Mfn2 and then partially restored the MAMs integrity. Additionally, VDR restored mitophagy was partially associated with MAMs integrity through Fundc1.

CONCLUSION

Activated VDR could contribute to restore mitophagy through Mfn2-MAMs-Fundc1 pathway in renal tubular cell. VDR could recover mitochondrial ATP, complex V activity and MAMs integrity, inhibit mitochondrial fission and mitochondrial ROS. It indicating that VDR agonists ameliorate renal tubulointerstitial fibrosis in diabetic rats partially via regulation of mitochondrial function.

Si-Ni-San Reduces Hepatic Lipid Deposition in Rats with Metabolic Associated Fatty Liver Disease by AMPK/SIRT1 Pathway

Background

Metabolic associated fatty liver disease (MAFLD) is a chronic disease characterized by excessive lipid deposition in the liver without alcohol or other clear liver-damaging factors. AMP-activated protein kinase (AMPK)/silencing information regulator (SIRT)1 signaling pathway plays an important role in MAFLD development. Si-Ni-San (SNS), a traditional Chinese medicine, has shown reducing hepatic lipid deposition in MAFLD rats, however, the underlying mechanisms of SNS are barely understood.

Purpose

The aim of this research was to investigate the mechanisms of SNS in reducing hepatic lipid deposition in MAFLD rats by regulating AMPK/SIRT1 signaling pathways.

Methods

The components of SNS were determined by high performance liquid chromatography with mass spectrometry (HPLC-MS) analysis. MAFLD rats were induced by high-fat and high-cholesterol diet (HFHCD), and treated by SNS. SNS-containing serum and Compound C (AMPK inhibitor) were used to treat palmitic acid (PA)-induced HepG2 cells. To elucidate the potential mechanism, lipid synthesis-related proteins (SREBP-1c and FAS), fatty acid oxidation (PPARα and CPT-1), and AMPK/SIRT1 signaling pathway (p-AMPK and SIRT1) were assessed by Western blot.

Results

SNS improved serum lipid levels, liver function and reduced hepatic lipid deposition in MAFLD rats. SNS-containing serum reduced lipid deposition in PA-induced HepG2 cells. SNS could up-regulate protein expressions of PPARα, CPT-1, p-AMPK and SIRT1, and down-regulate protein expressions of SREBP-1c and FAS. Similar effects of SNS-containing serum were observed in PA-induced HepG2 cells. Meanwhile, Compound C weakened the therapeutic effects of SNS-containing serum on lipid deposition.

Conclusion

SNS could reduce hepatic lipid deposition by inhibiting lipid synthesis and promoting fatty acid oxidation, which might be related with activating the AMPK/SIRT1 signaling pathway. This study could provide a theoretical basis for the clinical use of SNS to treat MAFLD.

Long-term and liver-selected ginsenoside C-K nanoparticles retard NAFLD progression by restoring lipid homeostasis

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent hepatic disease characterized as lipid accumulation, yet without any approved drug. And development of therapeutic molecules is obstructed by low efficiency and organ toxicity. Herein, we develop a long-term, low-toxic and liver-selected nano candidate, nabCK, to alleviate NAFLD. NabCK is simply composed by natural compound ginsenoside compound K (CK) and albumin. As a major metabolite of ginseng, ginsenoside CK has excellently modulating functions for lipid metabolism, but accompanied by an extremely poor bioavailability <1%. Albumin is a key lipid carrier secreted and metabolized by livers. Thereby, it can improve solubility and liver-localization of CK. In adipocytes and hepatocytes, nabCK prevents lipid deposition and eliminates lipid droplets. Transcriptomic analysis reveals that nabCK rectifies various pathways that involved in steatosis development, including lipid absorption, lipid export, fatty acid biosynthesis, lipid storage and inflammation. All these pathways are modulated by mTOR, the pivotal feedback sensor that is hyperactive in NAFLD. NabCK suppresses mTOR activation to restores lipid homeostasis. In high-fat diet (HFD) induced NAFLD mice, nabCK retards development of steatosis and fibrosis, coupling a protective effect on cardiac tissues from lipotoxicity. Together, nabCK is a safe and potent candidate to offer benefits for NAFLD treatment.

Plantamajoside modulates immune dysregulation and hepatic lipid metabolism in rats with nonalcoholic fatty liver disease via AMPK/Nrf2 elevation

Nonalcoholic fatty liver disease (NAFLD) is a hepatic metabolic syndrome with a rapidly increasing prevalence globally. Plantamajoside (PMS), a phenylethanoid glycoside component extracted from Plantago asiatica, has various biological properties. However, its effect on NAFLD remains unknown. The study aimed to explore the effect and mechanism of PMS on NAFLD in the high-fat diet (HFD)-feeding rats. PMS induced a decrease in body and liver weight, and the amelioration in the blood lipid parameters and pathological symptoms in HFD-feeding rats. The increase in the serum concentrations and the relative protein expressions of proinflammatory factors was decreased by the PMS treatment in HFD-induced NAFLD rats. Additionally, PMS reduced the excessive lipid vacuoles, and modified the relative expressions of proteins involved in the fatty acid synthesis and uptake in HFD-feeding rats. Mechanically, the downregulation of AMPK/Nrf2 pathway in HFD-feeding rats was restored by the PMS treatment. Inhibition of AMPK pathway reversed the PMS-induced the increase in the level of inflammatory factors, pathological symptoms, excessive lipid vacuoles, and the relative expression of proteins involved in the fatty acid synthesis and uptake. Collectively, PMS ameliorated immune dysregulation and abnormal hepatic lipid metabolism by activating AMPK/Nrf2 pathway in rats with NAFLD.

Vitamin D3 alleviates nonalcoholic fatty liver disease in rats by inhibiting hepatic oxidative stress and inflammation via the SREBP-1-c/ PPARα-NF-κB/IR-S2 signaling pathway

Introduction: Nonalcoholic fatty liver disease (NAFLD) is a chronic disease characterized by fat deposits in liver cells, which can lead to hepatitis and fibrosis. This study attempted to explore the protective effect of vitamin D3 (VitD) against NAFLD. Methods: Adult male albino rats were randomized into four separate groups: the negative control group was fed a standard rat chow; the positive group received a high-fat diet (20%) and 25% fructose water (NAFLD); the VitD control group was intramuscularly treated with VitD (1,000 IU/kg BW) 3 days per week for 10 weeks; and the NAFLD group was treated with VitD therapy. Biochemical and hepatic histological analyses were performed. Hepatic oxidative stress and inflammatory conditions were also studied. Hepatic expression of sterol regulatory element-binding protein 1-c (SREBP-1-c), peroxisome proliferator-activated receptor alpha (PPAR-α), and insulin receptor substrate-2 was analyzed by quantitative real-time polymerase chain reaction. Results and discussion: The NAFLD rats exhibited elevated terminal body weight, hepatic injury markers, dyslipidemia, glucose intolerance, and insulin resistance. Moreover, the NAFLD rats had increased SREBP-1-c expression and reduced PPAR-α and IRS-2 expressions. Histological analysis showed hepatic steatosis and inflammation in the NAFLD group. In contrast, VitD administration improved the serum biochemical parameters and hepatic redox status in NAFLD rats. Also, VitD treatment ameliorated hepatic inflammation and steatosis in the NAFLD group by decreasing the expression of SREBP-1-c and increasing the expression of PPAR-α. Overall, these results suggest that VitD could have a protective effect against NAFLD and its associated complication.

Protective Effect of Vitamin D against Hepatic Molecular Apoptosis Caused by a High-Fat Diet in Rats

The protective effects of vitamin D (VitD) in different diseases were studied. The liver is of great interest, especially with the presence of VitD receptors. A high-fat diet (HFD) is associated with many diseases, including liver injury. Consumption of saturated fatty acids triggers hepatic apoptosis and is associated with increased inflammation. We aimed in this study to investigate the protective effects of VitD on hepatic molecular apoptotic changes in response to an HFD in rats. Forty male Wistar albino rats were used and divided into four groups: control, HFD, control + VitD, and VitD-supplemented HFD (HFD + VitD) groups. After six months, the rats were sacrificed, and the livers were removed. RNA was extracted from liver tissues and used for the quantitative real-time RT-PCR of different genes: B-cell lymphoma/leukemia-2 (BCL2), BCL-2-associated X protein (Bax), Fas cell surface death receptor (FAS), FAS ligand (FASL), and tumor necrosis factor α (TNF-α). The results showed that an HFD increased the expression of the pro-apoptotic genes Bax, FAS, and FASL, and reduced the expression of the anti-apoptotic gene BCL2. Interestingly, a VitD-supplemented HFD significantly increased the BCL2 expression and decreased the expression of all pro-apoptotic genes and TNFα. In conclusion, VitD has a protective role against hepatic molecular apoptotic changes in response to an HFD.

An open-label, randomized, crossover study to evaluate the bioavailability of nanoemulsion versus conventional fat-soluble formulation of cholecalciferol in healthy participants

Background

Nanoemulsion preparations of cholecalciferol available in the market claim to have better bioavailability than the conventional fat-soluble cholecalciferol. However, limited data are available in humans for such preparations. We, therefore, compared the relative bioavailability of two formulations of 60,000 IU cholecalciferol (nanoemulsion oral solution, water-miscible vitamin D3 [test] vs soft gelatin capsules [reference]) in healthy adult participants.

Methods

In this randomized, open-label, two sequence, single-dose, two-way crossover study (CTRI/2018/05/013839), Indian participants aged 18-45 years received single dose of nanoemulsion and capsule formulations, under fasting conditions. Blood samples collected over 120 h were assessed to determine cholecalciferol concentrations. Pharmacokinetic parameters (area under the concentration-time curve up to 120 h [AUC0-120h], maximum observed drug concentration [Cmax], time to reach maximum drug concentration [Tmax], terminal half-life [T½el], and terminal elimination rate constant [Kel]) were estimated using baseline corrected data and analyzed using analysis of variance.

Results

Among the 24 eligible participants, the relative bioavailability of nanoemulsion was significantly higher than the capsules by 36% (p = 0.0001) based on AUC0-120h. Similarly, Cmax of the nanoemulsion was significantly higher by 43% (p = 0.0001) than that of the capsules. The intra-participant variability for AUC0-120h and Cmax were 23.22% and 26.51%, respectively. The Tmax, T½el, and Kel were comparable for both the formulations. No adverse effects were noted with either of the two formulations.

Conclusions

Nanoemulsion oral solution of cholecalciferol showed a greater bioavailability compared with soft gelatin capsules, under fasting conditions, in healthy human participants.

Canagliflozin interrupts mTOR-mediated inflammatory signaling and attenuates DMBA-induced mammary cell carcinoma in rats

BACKGROUND

Breast cancer prevalence has been globally increasing, therefore, introducing novel interventions in cancer treatment is of a significant importance. The present study was designed to investigate the anti-cancer effect of Canagliflozin (CNG) in an experimental model of DMBA-induced mammary carcinoma in female rats.

METHODS

18 female rats were divided into three experimental groups: Normal control, DMBA control, DMBA+ CNG treated group. DMBA (7.5 mg/kg) was injected subcutaneously in the mammary cells twice weekly for 4 weeks and CNG (10 mg/kg) was orally administered daily for an additional 3 weeks while DMBA control rats only received the vehicle for 3 weeks. Tumors' weight and volume were measured, BRCA-1 and TAC were quantified in serum samples, mTOR, caspase-1, NFκB, IL-1β, NLRP3, GSDMD and MDA were quantified in tumors' homogenates.

RESULTS

CNG treatment increased the BRCA-1 expression, suppressed mTOR inflammatory pathway, attenuated tumor inflammatory mediators; NLRP3, GSDMD, NFκB, IL-1β, suppressed the oxidative stress and inhibited tumor expression of the proliferation biomarker; Ki67.

CONCLUSION

CNG modulated mTOR-mediated signaling pathway and attenuated pyroptotic, inflammatory pathways, suppressed oxidative stress and eventually inhibited DMBA-induced mammary carcinoma proliferation.

Rho-kinase inhibition ameliorates non-alcoholic fatty liver disease in type 2 diabetic rats

Non-alcoholic fatty liver disease (NAFLD) is linked to type 2 diabetes mellitus (T2DM), obesity, and insulin resistance. The Rho/ROCK pathway had been involved in the pathophysiology of diabetic complications. This study was designed to assess the possible protective impacts of the Rho/Rho-associated coiled-coil containing protein kinase (Rho/ROCK) inhibitor fasudil against NAFLD in T2DM rats trying to elucidate the underlying mechanisms. Animals were assigned into control rats, non-treated diabetic rats with NAFLD, and diabetic rats with NAFLD that received fasudil treatment (10 mg/kg per day) for 6 weeks. The anthropometric measures and biochemical analyses were performed to assess metabolic and liver function changes. The inflammatory and oxidative stress markers and the histopathology of rat liver tissues were also investigated. Groups with T2DM showed increased body weight, serum glucose, and insulin resistance. They exhibited disturbed lipid profile, enhancement of inflammatory cytokines, and deterioration of liver function. Fasudil administration reduced body weight, insulin resistance, and raised liver enzymes. It improved the disturbed lipid profile and attenuated liver inflammation. Moreover, it slowed down the progression of high fat diet (HFD)-induced liver injury and reduced the caspase-3 expression. The present study demonstrated beneficial amelioration effect of fasudil on NAFLD in T2DM. The mechanisms underlying these impacts are improving dyslipidemia, attenuating oxidative stress, downregulated inflammation, improving mitochondrial architecture, and inhibiting apoptosis.

Bioavailability by design — Vitamin D3 liposomal delivery vehicles

Vitamin D3 deficiency has serious health consequences, as demonstrated by its effect on severity and recovery after COVID-19 infection. Because of high hydrophobicity, its absorption and subsequent redistribution throughout the body are inherently dependent on the accompanying lipids and/or proteins. The effective oral vitamin D₃ formulation should ensure penetration of the mucus layer followed by internalization by competent cells. Isothermal titration calorimetry and computer simulations show that vitamin D₃ molecules cannot leave the hydrophobic environment, indicating that their absorption is predominantly driven by the digestion of the delivery vehicle. In the clinical experiment, liposomal vitamin D₃ was compared to the oily formulation. The results obtained show that liposomal vitamin D₃ causes a rapid increase in the plasma concentration of calcidiol. No such effect was observed when the oily formulation was used. The effect was especially pronounced for people with severe vitamin D₃ deficiency.

Diacerein versus adipoRon as adiponectin modulators in experimentally-induced end-stage type 2 diabetes mellitus in rats

The objective of the present study is to evaluate and compare the possible anti-diabetic effects of adipoRon and diacerein in type 2 diabetes mellitus (T2DM) rats. T2DM is marked by impaired oxidative, inflammatory and metabolic signaling. Indeed, T2DM progression is associated with elevated HbA1C%, low adiponectin and insulin concentration. Moreover, in this study epididymal adipose tissue and soleus muscle MDA contents significantly escalated, while serum TAC and epididymal adipose Nrf2 significantly declined. Nevertheless, serum TNF-α, epididymal NLRP3, NF-κB, PPARγ and CD68 expression rose significantly with a parallel significant reduction in serum IL-10 and soleus muscle expression of IRS1. Both adipoRon and diacerein significantly improved adiponectin and insulin secretion with augmentation of anti-oxidant defenses and diminution of oxidative burden, with obvious anti-inflammatory consequences (p < 0.05). Thus, adipoRon and diacerein positively modulated adiponectin expression with down-regulation of NF-κB/NLRP3/PPARγ expression with subsequent improvement in glycemic control, inflammatory and oxidative signaling.

The Emerging Role of Nanomedicine in the Management of Nonalcoholic Fatty Liver Disease: A State-of-the-Art Review

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease that can lead to end-stage liver disease needing a liver transplant. Many pharmacological approaches are used to reduce the disease progression in NAFLD. However, current strategies remain ineffective to reverse the progression of NAFLD completely. Employing nanoparticles as a drug delivery system has demonstrated significant potential for improving the bioavailability of drugs in the treatment of NAFLD. Various types of nanoparticles are exploited in this regard for the management of NAFLD. In this review, we cover the current therapeutic approaches to manage NAFLD and provide a review of recent up-to-date advances in the uses of nanoparticles for the treatment of NAFLD.

Anti-aging properties of phytoconstituents and phyto-nanoemulsions and their application in managing aging-related diseases

Aging is spontaneous and inevitable process in all living beings. It is a complex natural phenomenon that manifests as a gradual decline of physiological functions and homeostasis. Aging inevitably leads to age-associated injuries, diseases, and eventually death. The research on aging-associated diseases aimed at delaying, preventing or even reversing the aging process are of great significance for healthy aging and also for scientific progress. Numerous plant-derived compounds have anti-aging effects, but their therapeutic potential is limited due to their short shelf-life and low bioavailability. As the novel delivery system, nanoemulsion can effectively improve this defect. Nanoemulsions enhance the delivery of drugs to the target site, maintain the plasma concentration for a longer period, and minimize adverse reaction and side effects. This review describes the importance of nanoemulsions for the delivery of phyto-derived compounds and highlights the importance of nanoemulsions in the treatment of aging-related diseases. It also covers the methods of preparation, fate and safety of nanoemulsions, which will provide valuable information for the development of new strategies in treatment of aging-related diseases.

Effect of vitamin D3 supplementation on hepatic lipid dysregulation associated with autophagy regulatory AMPK/Akt-mTOR signaling in type 2 diabetic mice

Vitamin D3 has been reported to protect liver against non-alcoholic fatty liver disease (NAFLD) by attenuating hepatic lipid dysregulation in type 2 diabetes mellitus (T2DM). However, the mechanism of vitamin D3 on hepatic lipid metabolism-associated autophagy in hyperglycemia-induced NAFLD remains yet to be exactly elucidated. C57BL/6J mice were intraperitoneally injected with 30 mg/kg of streptozotocin and fed a high-fat diet for induction of diabetes. All mice were administered with vehicle or vitamin D3 (300 ng/kg or 600 ng/kg) by oral gavage for 12 weeks. Histological demonstrations of the hepatic tissues were obtained by H&E staining and the protein levels related to lipid metabolism and autophagy signaling were analyzed by Western blot. Treatment with vitamin D3 improved insulin resistance, liver damage, and plasma lipid profiles, and decreased hepatic lipid content in the diabetic mice. Moreover, vitamin D3 administration ameliorated hepatic lipid dysregulation by downregulating lipogenesis and upregulating lipid oxidation under diabetic condition. Importantly, vitamin D3 treatment induced autophagy by activating AMP-activated protein kinase (AMPK), inactivating Akt and ultimately blocking mammalian target of rapamycin (mTOR) activation in the T2DM mice. Additionally, vitamin D3 was found to be effective in anti-apoptosis and anti-fibrosis in the liver of diabetic mice. The results suggested that vitamin D3 may ameliorate hepatic lipid dysregulation by activating autophagy regulatory AMPK/Akt-mTOR signaling in T2DM, providing insights into its beneficial effects on NAFLD in type 2 diabetic patients.

Fortification of Plant-Based Milk with Calcium May Reduce Vitamin D Bioaccessibility: An In Vitro Digestion Study

Many plant-based milks lack key micronutrients found in bovine milk, such as calcium and vitamin D. In this study, we fortified almond milk with these two micronutrients and used a standardized gastrointestinal model to examine the impact of product formulation on their bioaccessibility. The impact of different forms (CaCl₂ versus CaCO₃) and concentrations (0, 1, or 2 g per 240 mL) of calcium on the physicochemical properties, lipid digestibility, and vitamin D bioaccessibility was examined. Soluble calcium (CaCl₂) promoted particle aggregation by reducing the electrostatic repulsion, while colloidal calcium (CaCO₃) did not because there were fewer free calcium ions. High levels of calcium (soluble or insoluble) reduced vitamin D bioaccessibility, which was attributed to insoluble calcium soap formation in the small intestine. Calcium bioaccessibility was higher for CaCO₃ than CaCl₂. These findings are useful for the development of nutritionally fortified plant-based milks with improved physicochemical and nutritional properties.

Protective effect of nano vitamin D against fatty degeneration in submandibular and sublingual salivary glands: A histological and ultrastructural study

BACKGROUND

Poor nutritional habits and a low level of physical activity are associated with obesity, leading to increased caloric and fat intakes. A high-fat diet can significantly impact oral health through the accumulation of lipids in the salivary glands, which ultimately affect salivary gland function. Recently, an increasing number of supplement nano-formulations, such as nano vitamin D, have become available. However, only few studies have explored the effects of nano vitamin D on the maintenance of oral health.

OBJECTIVE

This study aimed to compare the histological effects of nano vitamin D to those of regular vitamin D on fatty degeneration in submandibular and sublingual salivary glands using a rat model.

METHODS

Twenty-four adult male albino Sprague-Dawley rats were divided into the following groups: untreated group, high-fat diet group, high-fat diet and regular vitamin D group, and high-fat diet and nano vitamin group.Thereafter, samples of the submandibular and sublingual salivary glands were dissected for histological and electron microscopic studies. Morphometric digital image analysis was used to quantitatively measure the changes in the size and number of acini and secretory granules.

RESULTS

Regular vitamin D had a partial protective effect. However, vitamin D could fully restore cellular structures to their normal state, thereby protecting against fatty degeneration of the salivary tissue and immune cell infiltration, particularly in the submandibular serous tissue. Nano vitamin D was more efficacious than regular vitamin D at restoring the number and size of submandibular serous secretory granules.

CONCLUSION

Employing nano vitamin D as a supplement to high-fat diets could protect against high-fat diet-induced salivary gland damage in rats.

The Evaluation of Drug Delivery Nanocarrier Development and Pharmacological Briefing for Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Current research indicates that the next silent epidemic will be linked to chronic liver diseases, specifically non-alcoholic fatty liver disease (NAFLD), which was renamed as metabolic-associated fatty liver disease (MAFLD) in 2020. Globally, MAFLD mortality is on the rise. The etiology of MAFLD is multifactorial and still incompletely understood, but includes the accumulation of intrahepatic lipids, alterations in energy metabolism, insulin resistance, and inflammatory processes. The available MAFLD treatment, therefore, relies on improving the patient's lifestyle and multidisciplinary pharmacotherapeutic options, whereas the option of surgery is useless without managing the comorbidities of the MAFLD. Nanotechnology is an emerging approach addressing MAFLD, where nanoformulations are suggested to improve the safety and physicochemical properties of conventional drugs/herbal medicines, physical, chemical, and physiological stability, and liver-targeting properties. A wide variety of liver nanosystems were constructed and delivered to the liver, only those that addressed the MAFLD were discussed in this review in terms of the nanocarrier classes, particle size, shape, zeta potential and offered dissolution rate(s), the suitable preparation method(s), excipients (with synergistic effects), and the suitable drug/compound for loading. The advantages and challenges of each nanocarrier and the focus on potential promising perspectives in the production of MAFLD nanomedicine were also highlighted.

β-patchoulene improves lipid metabolism to alleviate non-alcoholic fatty liver disease via activating AMPK signaling pathway

Non-alcoholic fatty liver disease (NAFLD) has been a leading cause of chronic metabolic disease, seriously posing healthy burdens to the public, whereas interventions available for it are limited to date. Patchouli oil had been reported to attenuate hepatic steatosis in our previous study. β-patchoulene (β-PAE) is a representative component separated from patchouli oil with multiple activities, but its effect against NAFLD is still unknown. To investigate the effect and potential mechanism of β-PAE on NAFLD, we used high fat diet (HFD) in vivo and free fatty acid (FFA) in vitro to induce hepatic steatosis in rats and L02 cells, respectively. Histological examination was evaluated via Hematoxylin-eosin and oil red O staining. The parameters for hepatic steatosis were estimated via biochemical kits, western blotting and quantitative real-time PCR. Compound C, the inhibitor of AMPK, was applied further to examine the precise mechanism of β-PAE on NAFLD. Our results indicated that β-PAE significantly attenuated HFD-induced weight gain, hepatic injury, lipid deposition in serum and hepatic tissue as well as FFA induced-lipid accumulation. Besides, β-PAE markedly improved the expression of AMP-activated protein kinase (AMPK) and its downstream factors which correlate with hepatic lipid synthesis and oxidation in vivo and in vitro. Nevertheless, Compound C abrogated the benefits derived from β-PAE in L02 cells. In conclusion, these results suggest that β-PAE exerts AMPK agonist-like effect to regulate hepatic lipid synthesis and oxidation, eventually prevent NAFLD progression.

Active vitamin D impedes the progression of non-alcoholic fatty liver disease by inhibiting cell senescence in a rat model

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) refers to an accumulation of excess fat in liver due to causes other than alcohol use. The relationship between vitamin D (VD) and NAFLD has been previously studied. Therefore, we aimed to explore the mechanism involved active VD regulating the progression of NAFLD by inhibiting cell senescence and to provide a potential approach for further nutritional treatment of NAFLD.

METHODS

Following the induction with high-fat diet and intraperitoneal injection of corn oil, the successfully established NAFLD rat models were treated with 1,25(OH)₂D₃ at 1μg/kg, 5μg/kg or 10μg/kg. Meanwhile, the levels of factors related to oxidative stress, cell senescence, the p53-p21 signaling pathway and inflammation in liver were determined. Then, cell senescence was also measured by using senescence-associated β-galactosidase (SAβ-gal) staining.

RESULTS

It was also found that active VD increased the concentration of VD in serum and VDR in liver of NAFLD rats, and alleviated hepatic fibrosis. Besides, treatment of 1,25(OH)₂D₃ at 1μg/kg, 5μg/kg or 10μg/kg reduced oxidative stress and inflammation, inhibited the p53-p21 signaling pathway and consequent cell senescence. Furthermore, treatment of 1,25(OH)₂D₃ at a dosage of 5μg/kg made the most impact on these factors.

CONCLUSION

Collectively, the evidences from this study demonstrated that active VD could alleviate the development of NAFLD through blocking the p53-p21 signaling pathway, which provided a novel nutritional therapeutic insight for NAFLD.

Self-microemulsifying oral fast dissolving films of vitamin D3 for infants: Preparation and characterization

Combining the advantages of self-microemulsifying technology and oral fast dissolving technology, a self-microemulsifying oral fast dissolving films (SMEOFDF) of vitamin D3 was developed in this study. The pseudoternary phase diagram of microemulsion was constructed using water titration method, and the formulation of films was optimized by orthogonal experimental design. The prepared SMEOFDF of vitamin D3 was a thin film, in which the liquid drops of self-microemulsion were embedded. It had good mechanical properties (thickness 166.7 ± 3.30 µm, tensile strength 38.45 ± 3.72 MPa, elongation 23.38 ± 4.23%, and folding endurance >200 times), and its disintegration time was about 18 ± 1.23 s. After being redissolved in water, microemulsion could form spontaneously, with particle size of 181.2 nm and zeta potential of 16.1 mV. The release profile of vitamin D from SMEOFDF could be well described by first-order equation.

Green tea polyphenols attenuate hepatic steatosis, and reduce insulin resistance and inflammation in high-fat diet-induced rats

Non‑alcoholic fatty liver disease (NAFLD) is characterized by hepatic steatosis, insulin resistance and inflammation; however, the exact pathogenesis of NAFLD is not fully understood. Green tea polyphenols (GTP) exhibit beneficial effects against metabolic syndrome. However, the effect of GTP on NAFLD remains largely unknown. The aim of the present study was to investigate the effects of GTP on NAFLD in high‑fat diet (HFD)‑induced rats. The NAFLD rat model was induced with a HFD for 8 weeks. A total of 30 adult male Sprague Dawley rats were randomly divided into three groups: i) Normal control group; ii) HFD group; and iii) HFD with GTP group. Hematoxylin and eosin and Oil Red O analyses were performed. The levels of alanine aminotransferase (ALT), aspartate amino-transferase (AST) and inflammatory cytokines in the serum, as well as oxidative stress markers and hepatic lipids in the liver were measured. In addition, parameters associated with glucose metabolism were also assessed. Western blotting and RT‑qPCR were used to determine the expression levels of 5' adenosine monophosphate‑activated protein kinase (AMPK). HFD‑induced rats exhibited features associated with NAFLD. GTP intervention significantly reduced serum ALT and AST levels. Fasting serum glucose, insulin resistance and hepatic lipid levels were all decreased in the GTP‑treated rats. GTP also significantly decreased the levels of TNF‑α, IL‑6 and malondialdehyde. In contrast, superoxide dismutase levels were increased in the liver. Furthermore, GTP also significantly increased phosphorylation of AMPK and attenuated histopathological changes indicative of injury in liver tissue. GTP has a protective effect on HFD‑induced hepatic steatosis, insulin resistance and inflammation, and the underlying mechanism may involve the AMPK pathway.

1α,25(OH)2 D3 alleviates high glucose-induced lipid accumulation in rat renal tubular epithelial cells by inhibiting SREBPs

Lipid accumulation is a vital event in the progression of diabetic nephropathy. 1,25-Dihydroxyvitamin D3 (1α,25(OH)₂ D₃ ) is considered to have a protective effect on diabetic nephropathy. However, it remains unclear whether 1α,25(OH)₂ D₃ can inhibit lipid accumulation, and the potential mechanisms responsible for lipid metabolism are incompletely understood. In this study, we evaluated the effects of 1α,25(OH)₂ D₃ on lipid metabolism in high glucose-exposed rat renal tubular epithelial NRK-52E cells. Results indicated that high glucose-enhanced lipid accumulation in NRK-52E cells and 1α,25(OH)₂ D₃ can remarkably decrease high glucose-induced lipid accumulation. Western blot showed that 1α,25(OH)₂ D₃ alleviated high glucose-induced upregulation of sterol regulatory element-binding protein-1c (SREBP-1c) and SREBP2, along with their established target genes fatty acid synthase (FASN) and hydroxymethylglutaryl CoA reductases (HMGCR). Overall, these findings suggest that 1α,25(OH)₂ D₃ downregulated the expressions of SREBPs to inhibit high glucose-induced lipid accumulation, which provides new sights into the protective effects of 1α,25(OH)₂ D₃ on diabetic nephropathy.

Targeted lipid nanoparticle delivery of calcitriol to human monocyte-derived macrophages in vitro and in vivo: investigation of the anti-inflammatory effects of calcitriol

Background

Vitamin D₃ possesses anti-inflammatory and modulatory properties in addition to its role in calcium and phosphate homeostasis. Upon activation, macrophages (M) can initiate and sustain pro-inflammatory cytokine production in inflammatory disorders and play a pathogenic role in certain cancers.

Purpose

The main purpose of this study was to encapsulate and specifically target calcitriol to macrophages and investigate the anti-inflammatory properties of calcitriol in vitro and in vivo.

Methods

In this study we have designed and developed near-infrared calcitriol PEGylated nanoparticles (PEG-LNP(Cal)) using a microfluidic mixing technique and modified lipid nanoparticles (LNPs) to target the M specific endocytic receptor CD163. We have investigated LNP cellular uptake and anti-inflammatory effect in LPS-induced M in vitro by flow cytometry, confocal microscopy and gene expression analyses. LNP pharmacodynamics, bio-distribution and organ specific LNP accumulation was also investigated in mice in vivo.

Results

In vitro, we observed the specific uptake of PEG-LNP(Cal)-hCD163 in human M, which was significantly higher than the non-specific uptake of control PEG-LNP(Cal)-IgG(h) in M. Pretreatment with encapsulated calcitriol was able to attenuate intracellular TNF-expression, and M surface marker HLA-DR expression more efficiently than free calcitriol in LPS-induced M in vitro. Encapsulated calcitriol diminished mRNA gene levels of TNF-, NF-B, MCP-1 and IL-6, while upregulating IL-10. TNF- and IL-6 protein secretion also decreased. In mice, an in vivo pharmacodynamic study of PEG-LNP(Cal) showed a rapid clearance of IgG and CD163 modified LNPs compared to PEG-LNP(Cal). Antibody modified PEG-LNP(Cal) accumulated in the liver, spleen and kidney, whereas unmodified PEG-LNP(Cal) accumulation was only observed in the liver.

Conclusion

Our results show that calcitriol can be effectively targeted to M. Our data confirms the anti-inflammatory properties of calcitriol and this may be a potential way to deliver high dose bioactive calcitriol to M during inflammation in vivo.

Bioavailability of nanoemulsion formulations vs conventional fat soluble preparations of cholecalciferol (D3) - An overview

Vitamin D deficiency is recognized as a pandemic affecting all ages and strata of population. The endogenous cutaneous synthesis of vitamin D is insufficient to maintain normal body requirement which necessitates the need for vitamin D supplementation or food-fortification. Conventional fat-soluble preparations of vitamin D have been traditionally used for prevention and therapeutic purposes. Recent advances in technology have enabled delivery of vitamin D through nanoemulsion formulations which ensure higher absorption and drug delivery. The following review briefly discusses the issues of bioavailability of nanoemulsion preparation of vitamin D vis-a-vis conventional fat soluble preparations.

An Argument for Vitamin D, A, and Zinc Monitoring in Cirrhosis

Malnutrition is prevalent in cirrhosis. Vitamin and mineral deficiencies, including vitamin D, vitamin A, and zinc, are common and have been shown to correlate with survival. Our aim was to review the mechanisms of vitamin D, vitamin A, and zinc deficiencies in cirrhosis and the clinical assessment of affected patients, their outcomes based on the current literature, and management. This is a narrative review including the relevant literature for cirrhosis and vitamin D, vitamin A, and zinc deficiencies. Vitamin D deficiency has important effects in cirrhosis, regardless of the cause of chronic liver disease.These effects include associations with fibrosis and outcomes such as infections, hepatocellular carcinoma, and mortality. Vitamin A deficiency is associated with liver disease progression to cirrhosis and clinical decompensation, including occurrence of ascites or hepatic encephalopathy. Zinc deficiency can lead to hepatic encephalopathy and impaired immune function. Such deficiencies correlate with patient survival and disease severity. Caution should be applied when replacing vitamin D, vitamin A, and zinc to avoid toxicity. Identification and appropriate treatment of vitamin and mineral deficiencies in cirrhosis may reduce specific nutritional and cirrhosis-related adverse events. Routine monitoring of vitamin A, vitamin D and zinc levels in cirrhosis should be considered.