Improvement in Diabetic Retinopathy through Protection against Retinal Apoptosis in Spontaneously Diabetic Torii Rats Mediated by Ethanol Extract of Osteomeles schwerinae C.K. Schneid

Abstract

Retinal apoptosis plays a critical role in the progression of diabetic retinopathy (DR), a common diabetic complication. Currently, the tight control of blood glucose levels is the standard approach to prevent or delay the progression of DR. However, prevalence of DR among diabetic patients remains high. Focusing on natural nutrients or herbal medicines that can prevent or delay the onset of diabetic complications, we administered an ethanol extract of the aerial portion of Osteomeles schwerinae (OSSCE), a Chinese herbal medicine, over a period of 17 weeks to spontaneously diabetic Torii (SDT) rats. OSSCE was found to ameliorate retinal apoptosis through the regulation of advanced glycation end product (AGE) accumulation, oxidative stress, and mitochondrial function via the inhibition of NF-κB activity, in turn, through the downregulation of PKCδ, P47phox, and ERK1/2. We further demonstrated in 25 mM glucose-treated human retinal microvascular endothelial cells (HRMECs) that hyperoside (3-O-galactoside-quercetin), quercitrin (3-O-rhamnoside-quercetin), and 2″-O-acetylvitexin (8-C-(2″-O-acetyl-glucoside)-apigenin) were the active components of OSSCE that mediated its pharmacological action. Our results provide evidence that OSSCE is a powerful agent that may directly mediate a delay in the development or disease improvement in patients of DR.

<p>Apigenin-Loaded Solid Lipid Nanoparticle Attenuates Diabetic Nephropathy Induced by Streptozotocin Nicotinamide Through Nrf2/HO-1/NF-kB Signalling Pathway</p>

“…Its low solubility, short half-life, low renal concentration, and minimal bioavailability hamper Apigenin uses. 12 Therefore, in laboratory animals, this research aimed to examine the attenuating effects of Apigenin-solid lipid nanoparticles(SLNPs) in diabetic nephropathy caused by streptozotocin (STZ) nicotinamide.…”

Therapeutic Effect of Abelmoschus manihot on Type 2 Diabetic Nonproliferative Retinopathy and the Involvement of VEGF

“…[17,18]. It was shown that quercetin has a dose-dependent effect in inhibiting proliferation of rhesus macaque choroid-retinal endothelial cells [19] and reducing apoptosis of retinal ganglion cell layer and whole retinal vessels in diabetic rats [20,21]. Meanwhile, the previous study has confirmed that quercetin could significantly inhibit the expression of retinal VEGF in diabetic rats [22].…”

Osteomeles schwerinae Extract and Its Major Compounds Inhibit Methylglyoxal-Induced Apoptosis in Human Retinal Pigment Epithelial Cells

“…Herbal extracts and natural compounds have traditionally been used to treat diabetes and diabetic complications [8,12,16,17]. Here, an OSSC extract and its maker compounds were tested for their inhibitory effects on apoptosis and its related mechanisms under toxic diabetic conditions in ARPE-19 cells.…”

“…In a previous study, the purities of maker compounds of OSSC extract were analyzed by HPLC [12]. Here, we evaluated whether the extract and its maker compounds could affect cell viability in MG-treated ARPE-19 cells.…”

“…Furthermore, this plant that has been used as a traditional Chinese medicine for the treatment of laryngopharyngitis, diarrhea, dysentery, folliculitis and hyperglycemia [10,11]. Previous studies have shown that OSSC ameliorates retinal endothelial cell apoptosis via the regulation of AGEs accumulation in the spontaneously diabetic torii rats [6,12]. Hyperoside, a compound of OSSC extract, has demonstrated significant inhibition of aldose reductase [13], the key enzyme in the polyol pathway during the pathogenesis of diabetic cataracts [14].…”