The protective effects of silymarin nanoemulsion on 5-fluorouracil-induced gastrointestinal toxicity in rats

Advancements in Nanoemulsion-Based Drug Delivery Across Different Administration Routes

Nanoemulsions (NEs) have emerged as effective drug delivery systems over the past few decades due to their multifaceted nature, offering advantages such as enhanced bioavailability, protection of encapsulated compounds, and low toxicity. In the present review, we focus on advancements in drug delivery over the last five years across (trans)dermal, oral, ocular, nasal, and intra-articular administration routes using NEs. Rational selection of components, surface functionalization, incorporation of permeation enhancers, and functionalization with targeting moieties are explored for each route discussed. Additionally, apart from NEs, we explore NE-based drug delivery systems (e.g., NE-based gels) while highlighting emerging approaches such as vaccination and theranostic applications. The growing interest in NEs for drug delivery purposes is reflected in clinical trials, which are also discussed. By summarizing the latest advances, exploring new strategies, and identifying critical challenges, this review focuses on developments for efficient NE-based therapeutic approaches.

Effects of dexpanthenol on 5-fluorouraci-induced nephrotoxicity, hepatotoxicity, and intestinal mucositis in rats: a clinical, biochemical, and pathological study

Background

5-fluorouracil (5-FU) is a broad-spectrum drug that has a wide range of side effects. Patients may experience severe comorbidities as a result of these toxic side effects, making it impossible for them to continue chemotherapy. Despite the fact that various molecules have been experimented, there is no literature data on the efficacy of dexpanthenol (DXP) for mitigating the toxic effects of 5-FU.

Objective

To investigate the protective effects of DXP on nephrotoxicity, hepatotoxicity, and intestinal toxicity induced by 5-FU in rats.

Methods

Twenty-eight male Wistar-Albino rats aged 16 weeks were randomly assigned to four groups. We created a rat model of intestinal mucositis, nephrotoxicity, and hepatotoxicity through intraperitoneal 5-FU (35 mg/kg for 4 d) injection. 500 mg/kg and 1000 mg/kg of DXP were administered to the treatment groups. The effects of dexpanthenol were evaluated clinically, biochemically, histopathologically, and immunohistochemically (inducible nitric oxide synthase [iNOS], cyclooxygenase-2 [COX-2], 8-hydroxyguanosine [8-OHdG], and nuclear factor kappa B [NF-κB]).

Results

5-FU caused a decrease in body weight and food intake, and an increase in diarrhea scores in rats. 5-FU led to significant disruptions in the hepatic biochemical markers (aspartate transaminase [AST], alanine transaminase [ALT], alkaline phosphatase [ALP], total bilirubin, direct bilirubin, and lactate dehydrogenase [LDH]), renal biochemical markers (blood urea nitrogen [BUN], creatinine, and uric acid), and protein and albumin, which are markers of both hepatic and renal functions. Severe pyknosis and mononuclear cell infiltrations were observed in the liver, and mononuclear cell infiltration and tubular degeneration in the kidneys. Jejunum and colon showed villous hyperemia and hemorrhage, respectively, along with mononuclear cell infiltration. Furthermore, 5-FU increased the immunohistochemical expressions of iNOS, COX-2, 8-OHdG, and NF-κB in the examined tissues. The administration of DXP at doses of 500 mg/kg and 1000 mg/kg demonstrated significant mitigation of the toxic effects induced by 5-FU on the liver, kidney, jejunum, and colon.

Conclusion

DXP showed protective effects against nephrotoxicity, hepatotoxicity, and intestinal toxicity caused by 5-FU. These findings suggest that DXP may serve as a potential therapeutic agent to alleviate the severe side effects of 5-FU chemotherapy, thereby improving patient tolerance and quality of life. Further clinical studies are warranted to validate these results and explore the translational potential of DXP in human cancer therapy.

Nobiletin reduces 5-FU-induced lung injury with antioxidative, anti-inflammatory and anti-apoptotic activities

Like other chemotherapeutic agents, 5-fluorouracil (5-FU) targets cancerous cells, but it also causes many unwanted side effects on healthy tissues and cells. Based on the undesirable effects of 5-FU, the aim of this study was to determine how 5-FU affects lung tissue and whether nobiletin has any protective effect. The study consisted of negative control, Nobiletin, 5-FU and Nobiletin + 5-FU groups. Nobiletin and Nobiletin + 5-FU groups received 10 mg/kg Nobiletin i.g. for 7 days. On day 8, 100 mg/kg 5-FU was administered i.p. to 5-FU and Nobiletin + 5-FU groups. Biochemical and immunohistochemical analyses were performed on the lung tissues dissected at the end of the study. 5-FU caused growth retardation, disturbed the oxidant-antioxidant balance by increasing MDA levels and decreasing GSH levels, triggered cellular apoptosis by increasing Bax and caspase-3 levels and decreasing Bcl-2, also increased lung tissue inflammation and damage by increasing NFκB and IL-1β levels. However, it was determined that Nobiletin prevented the disruption of the oxidant-antioxidant balance, showed significant anti-apoptotic effects, especially by reducing Bax levels and partially modulating caspase-3 and Bcl-2 levels, and also exhibited anti-inflammatory effects by reducing NFκB and IL-1β levels and supported the normal development of animals. Our results showed that nobiletin pretreatment showed anti-inflammatory activity by inhibiting the NFκB pathway in 5-FU-induced lung injury, suppressed oxidative stress with its antioxidant activity and was effective in modulating cellular apoptosis with its anti-apoptotic activity. In conclusion, Nobiletin has been shown to have an important potential in reducing fluorouracil-induced tissue damage by acting through multiple pathways.

Silymarin and Inflammation: Food for Thoughts

Inflammation is a vital defense mechanism, creating hostile conditions for pathogens, preventing the spread of tissue infection and repairing damaged tissues in humans and animals. However, when inflammation resolution is delayed or compromised as a result of its misregulation, the process proceeds from the acute phase to chronic inflammation, leading to the development of various chronic illnesses. It is proven that redox balance disturbances and oxidative stress are among major factors inducing NF-κB and leading to over-inflammation. Therefore, the anti-inflammatory properties of various natural antioxidants have been widely tested in various in vitro and in vivo systems. Accumulating evidence indicates that silymarin (SM) and its main constituent silibinin/silybin (SB) have great potential as an anti-inflammation agent. The main anti-inflammatory mechanism of SM/SB action is attributed to the inhibition of TLR4/NF-κB-mediated signaling pathways and the downregulated expression of pro-inflammatory mediators, including TNF-α, IL-1β, IL-6, IL-12, IL-23, CCL4, CXCL10, etc. Of note, in the same model systems, SM/SB was able to upregulate anti-inflammatory cytokines (IL-4, IL-10, IL-13, TGF-β, etc.) and lipid mediators involved in the resolution of inflammation. The inflammatory properties of SM/SB were clearly demonstrated in model systems based on immune (macrophages and monocytes) and non-immune (epithelial, skin, bone, connective tissue and cancer) cells. At the same time, the anti-inflammatory action of SM/SB was confirmed in a number of in vivo models, including toxicity models, nonalcoholic fatty liver disease, ischemia/reperfusion models, stress-induced injuries, ageing and exercising models, wound healing and many other relevant model systems. It seems likely that the anti-inflammatory activities of SM/SB are key elements on the health-promoting properties of these phytochemicals.