Zerumbone, a Phytochemical of Subtropical Ginger, Protects against Hyperglycemia-Induced Retinal Damage in Experimental Diabetic Rats

Abstract

Diabetic retinopathy (DR), the most ordinary and specific microvascular complication of diabetes, is a disease of the retina. Zerumbone (ZER) is a monocyclic sesquiterpene compound, and based on reports, it is the predominant bioactive compound from the rhizomes of Zingiber zerumbet. The aim of the current study is to evaluate the protective effect of zerumbone against DR in streptozotocin (STZ)-induced diabetic rats. STZ-diabetic rats were treated with ZER (40 mg/kg) once a day orally for 8 weeks. ZER administration significantly (p < 0.05) lowered the levels of plasma glucose (32.5% ± 5.7% lower) and glycosylated hemoglobin (29.2% ± 3.4% lower) in STZ-diabetic rats. Retinal histopathological observations indicated that disarrangement and reduction in thickness of retinal layers were reversed in ZER-treated diabetic rats. ZER downregulated both the elevated levels of advanced glycosylated end products (AGEs) and the higher levels of the receptors for AGEs (RAGE) in retinas of diabetic rats. What’s more, ZER significantly (p < 0.05) ameliorated diabetes-induced upregulation of tumor necrosis factor-α, interleukin (IL)-1 and IL-6. ZER also attenuated overexpression of vascular endothelial growth factor and intercellular adhesion molecule-1, and suppressed activation of nuclear factor (NF)-κB and apoptosis in the retinas of STZ-diabetic rats. Our results suggest ZER possesses retinal protective effects, which might be associated with the blockade of the AGEs/RAGE/NF-κB pathway and its anti-inflammatory activity.

Dietary zerumbone, a sesquiterpene, ameliorates hepatotoxin‐mediated acute and chronic liver injury in mice

“…Recent studies have shown that ZER can attenuate high‐fat diet‐induced hyperlipidemia and fatty liver through modulation of lipid metabolism (Tzeng, Liou, Chang, & Liu, ; Tzeng, Lu, Liou, Chang, & Liu, ). ZER also possesses protective effects on high glucose‐induced apoptosis in pancreatic β‐cells (Wang et al, ) and diabetes‐mediated retinal damage (Tzeng, Liou, Tzeng, & Liu, ).…”

Carbonyl Activation in Electrophilic Polyene Cyclizations: A Toolbox for the Design of Isoprenoid Libraries

“…], [7] and the contribution of the transannularly conjugated dipolar formula 3 to its structure and chemistry, [8] made us wonder whether the presence of the carbonyl group could provide an electronic finesse and/or the necessary preorganization of the cycloundecatriene system to trigger aconcerted transannular cyclization and breach the Eolefin barrier. [9] Since 2 shows potent activity in animal models of human chronic degenerative diseases like cancer, [10] diabetes, [11] and arthritis, [12] and is also of relevance for perfumery, [13] the structural context for probing this concept was not only mechanistically appealing,but also relevant for medicinal and lifestyle related applications. [9] Since 2 shows potent activity in animal models of human chronic degenerative diseases like cancer, [10] diabetes, [11] and arthritis, [12] and is also of relevance for perfumery, [13] the structural context for probing this concept was not only mechanistically appealing,but also relevant for medicinal and lifestyle related applications.…”

“…[4] To avoid the formation of endocyclic E-configured double bonds in unsaturated rings smaller than cyclooctene,asituation topologically impossible, [5] the cyclization of 1,a na ll-E-configured cyclo-undecatriene,m ust follow ap athway that involves all three double bonds in ac oncerted fashion. [9] Since 2 shows potent activity in animal models of human chronic degenerative diseases like cancer, [10] diabetes, [11] and arthritis, [12] and is also of relevance for perfumery, [13] the structural context for probing this concept was not only Figure 1. [4] Ther eady availability of the 8-oxo derivative of ahumulene (zerumbone; 2)f rom at ropical ginger [Zingiber zerumbet (L.) Roscoe ex Sm.…”

Carbonyl Activation in Electrophilic Polyene Cyclizations: A Toolbox for the Design of Isoprenoid Libraries

“…We envisioned that, after carbonyl activation with an electrophilic reagent ( A , Figure ), the crossed dienone system could undergo electrocyclization in a Nazarov fashion to an allyl cation ( B ), thus in effect removing the E ‐olefin barrier to intramolecular cyclization and paving the way to an interrupted Nazarov reaction course (Figure ) . Since 2 shows potent activity in animal models of human chronic degenerative diseases like cancer, diabetes, and arthritis, and is also of relevance for perfumery, the structural context for probing this concept was not only mechanistically appealing, but also relevant for medicinal and lifestyle related applications.…”