The Antioxidant Effect Of Curcumin Part 1

Please contact oscar.xiao@wecistanche.com for more information

Abstract: Background: There is a growing interest in the correlation between antioxidants and periodontal disease. In this study, we aimed to investigate the effect of oxidative stress and the impact of two antioxidants, curcumin, and rutin, respectively, in the etiopathology of experimentally induced periodontitis in diabetic rats. Methods: Fifty Wistar albino rats were randomly divided into five groups and were induced with diabetes mellitus and periodontitis: (1)(CONTROL)—control group, (2)(DPP)—experimentally induced diabetes mellitus and periodontitis, (3) (DPC)—experimentally induced diabetes mellitus and periodontitis treated with curcumin (C),(4)(DPR)—experimentally induced diabetes mellitus and periodontitis treated with rutin (R) and (5)(DPCR)—experimentally induced diabetes mellitus and periodontitis treated with Cand R. We evaluated malondialdehyde (MDA) as a biomarker of oxidative stress and reduced glutathione (GSH), oxidized glutathione (GSSG), GSH/GSSG and catalase(CAT) as biomarkers of the antioxidant capacity in blood harvested from the animals we tested. The MDA levels and1 CAT activities were also evaluated in the gingival tissue. Results: The control group effect was statistically significantly different from any other groups, regardless of whether or not the treatment was applied. There was also a significant difference between the untreated group and the three treatment groups for variables MDA, GSH, GSSG, GSH/GSSG, and CAT. There was no significant difference in the mean effect for the MDA, GSH, GSSG, GSH/GSSG, and CAT variables in the treated groups of rats with curcumin, rutin, and the combination of curcumin and rutin. Conclusions: The oral administration of curcumin and rutin, single or combined, could reduce oxidative stress and enhance the antioxidant status in hyperglycemic periodontitis rats.

Keywords: antioxidant effect; curcumin; rutin; periodontitis; diabetes; oxidative stress

Please click here to know more

1.Introduction

Diabetes is described as a"serious, chronic disease that occurs either when the pancreas does not produce enough insulin, or when the body cannot use the insulin it produces effectively" [1]. Type 1 and type 2 are the two most common forms of diabetes [2]. Type 1 diabetes is caused by the autoimmune destruction of pancreatic β cells in genetically predisposed individuals and results in severe insulin deficiency requiring insulin treatment It is typically considered a childhood and adolescence disease, but it can occur at any age [3]. Type 2 diabetes mellitus (T2DM) is the most common endocrine disorder and has an increasing incidence worldwide. This is a serious public health concern due to the need for lifelong care, premature death, and the fact that it remains incurable[4].

Diabetes is one of the major risk factors for periodontitis [5]. Less clear is the impact of periodontal diseases on the glycemic control of diabetes and the mechanisms by which it occurs. Inflammatory periodontal diseases may increase insulin resistance in a way similar to obesity, leading to an increase in glycemic control [6].

Cistanche can improve immunity

Periodontal disease is a pathological entity with a high incidence and a wide range of symptoms that may develop into severe forms [7]. Periodontitis, every time, inevitably leads to significant and progressive damage to periodontal support tissue as a high-incidence disease. The conventional treatment methods for regenerating lost periodontal tissue currently consist of basic periodontal therapy, periodontal flap surgery and guided tissue regeneration [8-10]. The mechanism for healing is based on the formation of conjunctive epithelium, which is difficult to achieve, for the successful regeneration of functional periodontal tissue. In recent years, the technology for periodontal tissue engineering has evolved, and it is based on three aspects: seed cells (PDLSCs—human periodontal ligament stem cells), scaffolds and growth factors, which are expected to achieve functional periodontal tissue regeneration [11,12]. It has been speculated that rutin, as a typical flavonoid might improve the characteristics of PDLSCs and enhance the regeneration ability of the periodontal tissue in an inflammatory environment [13]. Several studies have confirmed the beneficial effects of rutin in anti-inflammatory, antitumor, and antioxidative activities; cell proliferation; apoptosis; cistanche beneficios differentiation and wound healing and have speculated that it may even enhance the ability of periodontal tissue to regenerate in an inflammatory environment[13-16].

Rutin is a glycoside that exhibits multiple pharmacological activities, including antidiabetic, antioxidant, and anti-inflammatory activities in different models of rodents by scavenging free radicals and inhibiting lipid peroxidation, preventing streptozotocin (STZ)-induced oxidative damage, and by protecting pancreatic B cells to increase insulin secretion and lower blood glucose levels [17,18]. A chronic increase in blood glucose (associated with diabetes mellitus—DM) is a central factor in the production of reactive species that promote cellular damage and contribute to the development and progression of diabetic complications[19]. Rutin has been associated with the improvement in glycemic control in patients with diabetes, suggesting that it might be a required nutritional supplement in these patients [20,21]. Nang et al.,2017 suggested that rutin may be a candidate agent that could be an alternative to the prevention and treatment of vascular disease in diabetes. These protective effects of rutin may have resulted from its ability to decrease the production of reactive oxygen species (ROS) and malondialdehyde (MDA)and to enhance the antioxidant enzyme activity of catalase(CAT) [22,23].

Curcumin, from the root of the turmeric plant Curcuma longa, is an extended pseudo symmetric polyphenol (diferuloylmethane) [24-26]. Zhou et al. showed that curcumin prevents bone loss in an experimental periodontitis model [27]. In association with studies that do demonstrate an effect on the prevention of bone loss, these investigations have shown that curcumin has a profound effect on inflammation by significantly reducing the development of inflammatory infiltrates within the periodontal lesion while simultaneously stimulating an increase in the collagen content, as well as an increase in the number of fibroblastic cells within the periodontium and associated lesions when curcumin was administered daily to rats with experimentally induced periodontitis [27,28].

2. Results

The malondialdehyde (MDA) and oxidized glutathione (GSSG)levels were signifi-cantly decreased (p <0.05) as compared to the placebo group (DPP) after administrating rutin and curcumin. The combination between curcumin and rutin (DPCR)had a more positive effect on the MDA levels compared to just rutin (DPR)and a comparable effect compared to curcumin alone (DPC). Administrating curcumin alone (DPC group) had a more positive effect on reducing the GSSG levels as compared to rutin (DPR) and curcumin and rutin(DPCR)(Figures 1-3).

The glutathione (GSH), GSH/GSSC (glutathione/oxidized glutathione), and catalase (CAT) activities significantly increased (p<0.05) as compared to the placebo group (DPP). The administration of curcumin had a more positive effect on the GSH levels compared to the administration of curcumin and rutin (DPCR) or rutin (DPR). Rutin (DPR)had a more positive effect compared to rutin and curcumin (DPCR) on the GSH levels.

The levels for GSH/GSSG were increased when comparing the curcumin group (DPC)with DPR and DPCR. The combination of curcumin and rutin (DPCR) had a more positive effect than rutin alone(DPR).

The combination of curcumin and rutin (DPCR) increased the CAT levels compared to curcumin (DPC) or rutin (DPR) alone. Administrating curcumin had a more positive effect than administrating rutin.

The results of the ANOVA test (Table 1) confirmed that there were significant differences in the mean values for all five groups of rats under investigation for all variables. It could also be seen in the high values of the Ftest for all variables. The total sum of squares explained the variations of MDA, GSH, GSSG, GSH/GSSG, and CAT due to the changes in treatment from the control group to those with diabetes mellitus and periodontitis who were not treated with curcumin, rutin or a combination of both.

Scheffe's test was performed to assess which antioxidant has no impact on the mean variable values presented in Table2.

The control group effect was statistically significantly different from any other group, regardless of whether or not the treatment was applied. There was also a significant difference between the untreated group and the three treatment groups for variables MDA, GSH, GSSG, GSH/GSSG, and CAT. There was no significant difference in the mean effect between groups 3 and 4,3 and 5 and 4 and 5. In other words, curcumin, rutin, and the combination of the two had a positive effect on the treatment of the sick group of rats.

This article is extracted from Molecules 2021, 26, 1332. https://doi.org/10.3390/molecules26051332 https://www.mdpi.com/journal/molecules