The bioflavonoid hispidulin effectively attenuates T helper type 2-driven allergic lung inflammation in the ovalbumin-induced allergic asthma mouse model

BACKGROUND

Allergic asthma affects nearly 300 million people worldwide and causes ahigh burden of disability and death. Effective treatments rely heavily on corticosteroids, which are associated with various complications. So, the alternative treatment is of significance. Hispidulin is a bioflavonoid found in herbs that were used in traditional medicine to treat inflammatory diseases, including asthma. This study aims to investigate the efficacy of hispidulin compound in the treatment of allergic lung inflammation using the mouse model of allergic asthma.

METHODS

BALB/c mice were sensitized and challenged with chicken egg ovalbumin. Cells and cytokines from bronchoalveolar lavage (BAL) fluid were examined. Lung tissues were collected for histologic study. Mouse splenic CD4+ cells were cultured to observe the effect of hispidulin on T-helper 2 (Th2) cell differentiation in vitro.

RESULTS

Hispidulin treatment could alleviate allergic airway inflammation as evidenced by a significant reduction in the inflammatory cell count and Th2 cytokines interleukin (IL)-4, IL-5, IL-13 in BAL fluid. Histologic examination of lung tissues revealed lower inflammatory cell infiltration to the bronchi and less airway goblet cell hyperplasia in the treatment group compared to the control group. At the cellular level, hispidulin (25, 50, and 100 μM) was found to directly suppress the differentiation and proliferation of Th2 cells and to suppress the production of Th2 cytokines, such as IL-4, IL-5, and IL-13, in vitro.

CONCLUSIONS

Hispidulin treatment was shown to effectively decrease type 2 lung inflammation in an ovalbumin-induced allergic asthma mouse model by directly suppressing Th2 cell differentiation and functions.

A comparative study of optimized naringenin nanoformulations using nano-carriers (PLA/PVA and zein/pectin) for improvement of bioavailability

Naringenin, a lipophilic flavanone of citrus fruits, was encapsulated for enhanced bioavailability using biodegradable polymers of polylactic acid/polyvinyl alcohol (PLA/PVA) as well as zein/pectin as P/P-Nar-NPs and Z/P-Nar-NPs, respectively. The formulation variables were optimized using response surface methodology to achieve smaller particle size with higher surface charge and encapsulation efficiencies. The optimized formulations were physically characterized by SEM, FTIR, TGA and XRD techniques. Compared to Z/P-Nar-NPs, the P/P-Nar-NPs had better encapsulation efficiency and sustained release of naringenin under simulated gastrointestinal conditions. Furthermore, the oral administration of single dose of free and nanoforms of naringenin in rats (90 mg/kg b.wt) showed higher efficacy of PLA/PVA in improving the relative bioavailability of naringenin (4.7-fold) as compared to the zein/pectin polymer (1.9-fold). Overall, the present study provides insights into the formulation performance of the encapsulated bioactive compound under different polymeric matrices.

The effects of hesperidin on stricture formation in corrosive esophageal burns: an experimental study

AIM/BACKGROUND

Esophageal strictures in children that develop as a result of accidental ingestion of corrosive substances remain an important health problem. The purpose of this study is to determine the effects of Hesperidin, an effective bioflavonoid in the proliferative and exudative phase of inflammation, on the stricture formation in corrosive esophageal burns.

METHODS

Experimental esophageal burns in rats were created using a modified Gehanno and Guedon model with 20% NaOH. Rats were divided into 5 groups. In the Sham group, the distal esophagus was prepared and cannulated according to the model, but no NaOH was administrated. The esophageal burn was created with NaOH in the other groups. The burned groups were divided into two groups as untreated (T¹⁴, T²¹) and treated with 100 mg/kg/day Hesperidin (H¹⁴, H²¹) intraperitoneally, and these groups were divided into two according to their sacrification periods (14 and 21 days). Inflammation, fibrosis, and necrosis were graded by histopathological evaluation in all groups. The efficacy of treatment was evaluated using the weight of rats, stenosis index, and histopathological parameters.

RESULTS

Histopathologic damage scores such as inflammation, necrosis, and fibrosis were lower in the H¹⁴ and H²¹ groups and higher in the T¹⁴ and T²¹ groups. And also stenosis index was found higher in T¹⁴ and T²¹ groups (p < 0.05), while it was similar to the Sham group in H¹⁴ and H²¹ groups. No statistically significant difference was found between the H¹⁴ and H²¹ groups in terms of stenosis index. When weights of the rats at the beginning and end of the experiment were compared, weights of the H¹⁴ and H²¹ groups and the Sham group were similar. There was a significant decrease in the weight of the rats in the T¹⁴ and T²¹ groups (p < 0.001).

CONCLUSIONS

This study is the first to use Hesperidin in preventing esophageal damage in an esophageal caustic burn model. It was shown that Hesperidin was effective in reducing macroscopic and microscopic histopathologic damage in the corrosive esophageal burn model, preventing the stricture formation, and has positive effects on nutrition in rats with an esophageal burn.

Naringin Confers Protection against Psychosocial Defeat Stress-Induced Neurobehavioral Deficits in Mice: Involvement of Glutamic Acid Decarboxylase Isoform-67, Oxido-Nitrergic Stress, and Neuroinflammatory Mechanisms

Psychosocial stress has been widely reported to contribute to psychiatric disturbances. Perturbations in the enzymes of GABAergic and cholinergic systems have been implicated as precursors in different stress-related neuropsychiatric diseases. Targeting glutamic acid decarboxylase-67 kDa (GAD67) and acetylcholinesterase (AChE) via oxidative, nitrergic, and neuroinflammatory mechanisms have been recognized as prospective strategies for the prevention of psychosocial stress-induced behavioral impairments. Naringin, a neuro-active flavonoid compound isolated from citrus fruits, has been shown to produce memory-enhancing, antiepileptic, antidepressant, and anti-inflammatory activities similarly to ginseng, a very potent adaptogen. In this communication, we assessed the effect of naringin on social-defeat stress (SDS)-induced behavioral, GABAergic, cholinergic, oxidative, nitrergic, and neuroinflammatory changes in mice using the resident-intruder paradigm. The intruder male mice were culled into six groups. Groups 1 and 2 (normal- and SDS-controls) received sterile saline, groups 3-5 were given naringin (25-100 mg/kg, i.p.) whereas group 6 had ginseng (50 mg/kg, i.p.) daily for 14 days, but followed by 10 min SDS (physical and psychological) exposure to groups 2-6 with aggressor-resident mice. Behavioral effects using Y-maze, elevated-plus maze, sociability, and tail-suspension tests were assessed on day 14. GAD67, AChE enzymes, and biomarkers of oxidative, nitrergic, and neuroinflammatory changes were assayed in the striatum, prefrontal cortex, and hippocampus. Naringin and ginseng reversed all SDS-induced behavioral impairments. Naringin increased the levels of GAD67 and decreased AChE activities in the striatum, prefrontal cortex, and hippocampus. Furthermore, naringin reduced pro-inflammatory cytokines (TNF-α, IL-6), malondialdehyde, nitrite concentrations, and increased glutathione levels in a region-dependent manner. Our study suggests that naringin attenuated SDS-induced behavioral endophenotypes of neuropsychiatric disease through increased GAD67 synthesis, inhibition of AChE activity, oxidative, nitrergic stress, and neuroinflammatory processes in stress-sensitive brain regions.

Quercetin inhibits prostate cancer by attenuating cell survival and inhibiting anti-apoptotic pathways

Background

Despite recent advances in diagnosis and treatment, prostate cancer (PCa) remains the leading cause of cancer-related deaths in men. Current treatments offered in the clinics are often toxic and have severe side effects. Hence, to treat and manage PCa, new agents with fewer side effects or having potential to reduce side effects of conventional therapy are needed. In this study, we show anti-cancer effects of quercetin, an abundant bioflavonoid commonly used to treat prostatitis, and defined quercetin-induced cellular and molecular changes leading to PCa cell death.

Methods

Cell viability was assessed using MTT. Cell death mode, mitochondrial outer membrane potential, and oxidative stress levels were determined by flow cytometry using Annexin V-7 AAD dual staining kit, JC-1 dye, and ROS detection kit, respectively. Antibody microarray and western blot were used to delineate the molecular changes induced by quercetin.

Results

PCa cells treated with various concentrations of quercetin showed time- and dose-dependent decrease in cell viability compared to controls, without affecting normal prostate epithelial cells. Quercetin led to apoptotic and necrotic cell death in PCa cells by affecting the mitochondrial integrity and disturbing the ROS homeostasis depending upon the genetic makeup and oxidative status of the cells. LNCaP and PC-3 cells that have an oxidative cellular environment showed ROS quenching after quercetin treatment while DU-145 showed rise in ROS levels despite having a highly reductive environment. Opposing effects of quercetin were also observed on the pro-survival pathways of PCa cells. PCa cells with mutated p53 (DU-145) and increased ROS showed significant reduction in the activation of pro-survival Akt pathway while Raf/MEK were activated in response to quercetin. PC-3 cells lacking p53 and PTEN with reduced ROS levels showed significant activation of Akt and NF-κB pathway. Although some of these changes are commonly associated with oncogenic response, the cumulative effect of these alterations is PCa cell death.

Conclusions

Our results demonstrated quercetin exerts its anti-cancer effects by modulating ROS, Akt, and NF-κB pathways. Quercetin could be used as a chemopreventive option as well as in combination with chemotherapeutic drugs to improve clinical outcomes of PCa patients.

Safety evaluation of naringenin upon experimental exposure on rat gastrointestinal epithelium for novel optimal drug delivery

OBJECTIVE

To assess the effect of naringenin on the intestinal biochemical composition, function and histology for gastrointestinal toxicity since it has not yet been adequately exploited for safety through standard assays.

METHODS

Here, we describe naringenin (1 mM, 10 mM and 100 mM, respectively) or sodium deoxycholate (10 mM) effects on isolated brush border membrane from intestinal segments with single pass intestinal perfusion using lactate dehydrogenase, alkaline phosphatase and protein assays. MTT assay was used for cytotoxicity studies. Everted gut sac studies were used for evaluating the transport of nutrients across the intestinal segments. Lucifer yellow was used for paracellular permeability, followed by histological changes and surface characteristic studies of intestinal sacs.

RESULTS

The results indicated no significant alterations with naringenin, although significant (p < 0.01) changes were noticed with sodium deoxycholate in the activity of the rat intestinal brush border associated enzymes such as LDH, followed by intact cell viability with marked decrease in the villi height of the intestinal segments.

CONCLUSIONS

These observations indicate that naringenin was harmless upon exposure to rat gastrointestinal epithelium, clearly demonstrating the potential use of naturally occurring bioflavonoid as safe and novel pharmaceutical adjuvant in oral dosage forms as P-gp inhibitor.