Compared with carbon nanotubes and graphene, graphene oxide (GO) exhibits excellent water solubility and biocompatibility in addition to the characteristic G band in Raman spectra. Therefore GO might be able to act as a flexible Raman probe to image cells or tissues through Raman mapping. However, the weak intensity of the G band restricts such applications of GO. Here we decorated GO with Au nanoparticles and found that the Raman intensity of GO in aqueous dispersions were remarkably enhanced by the surface enhancement effect. Therefore, rapid Raman imaging for Hela 229 cells was realized using Au/GO hybrids as Raman probes. The cell internalization mechanism of GO and Au/GO hybrids were also studied using Raman imaging. An endocytosis pathway was proposed from the results. In addition, the aqueous dispersions of Au/GO hybrids are stable for several weeks. Therefore, relying on the surface enhancement effect of Au nanoparticles, GO exhibits great potential as a general Raman imaging tool for biosystems.

Spermatogenic dysfunction is one of the major secondary complications of diabetes. L. barbarum polysaccharide (LBP) has long been considered to possess anti-apoptotic activities and antioxidant, anti-inflammatory and fertility-enhancing properties in traditional medical practices in China. The aim of the current study was to seek out scientific evidence to determine if LBP also contributes to the recovery from spermatogenic dysfunction in diabetic individuals. We investigated whether the oral administration of LBP in streptozotocin (STZ)-induced type-1 diabetic male mice would reverse spermatogenic dysfunction and improve histological damage in testes. After the oral administration of LBP (10, 20 or 40 mg kg, respectively), sildenafil citrate (5 mg kg) or saline for 62 consecutive days, the sperm parameters were analyzed. Macroscopic and microscopic changes in the reproductive organs, including their weight, and photomicroscope and electronmicroscope images were also assessed. In addition, the antioxidant capacity and levels of malondialdehyde in the testes were determined according to the instructions provided with the assay kits and the expression of the apoptosis-related proteins, Caspase-3, Bax and Bcl-2, in the testes was analyzed using western-blot analysis. LBP treatment of diabetic mice considerably recovered the sperm parameters, increased the weight of the reproductive organs, ameliorated their histological appearance and increased antioxidant enzyme activity to different degrees. Moreover, our data also showed a marked decrease in Caspase-3 expression and an increase in the ratio of Bcl-2/Bax 43 after LBP administration (40 mg kg) when compared to the diabetic group. These results demonstrate that LBP exerts protective effects on diabetes induced male spermatogenic dysfunction, which is likely to be mediated through increasing antioxidant enzyme activities and inhibiting cell death.

Matrine, an active constituent of the Chinese herb, Sophora flavescens Ait., and it is known for its antioxidant, anti-inflammatory and antitumor activities. It has been demonstrated that matrine exerts protective effects against heart failure by decreasing the expression of caspase-3 and Bax, and increasing Bcl-2 levels. In this study, we aimed to determine whether these protective effects of matrine can be applied to cerebral ischemia. Following 7 successive days of treatment with matrine (7.5, 15 and 30 mg/kg) and nimodipine (1 mg/kg) by intraperitoneal injection, male Institute of Cancer Research (ICR) mice were subjected to middle cerebral artery occlusion (MCAO). Following reperfusion, the neurobehavioral score and brain infarct volume were estimated, and morphological changes were analyzed by hematoxylin and eosin (H&E) staining and electron microscopy. The percentage of apoptotic neurons was determined by flow cytometry. The levels of oxidative stress were assessed by measuring the levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), and the total antioxidant capacity (T-AOC). Western blot analysis and immunofluorescence staining were used to examine the expression of the apoptosis-related proteins, caspase-3, Bax and Bcl-2. Our results revealed that pre-treatment with matrine significantly decreased the infarct volume and improved the neurological scores. Matrine also reduced the percentage of apoptotic neurons and relieved neuronal morphological damage. Furthermore, matrine markedly decreased the MDA levels, and increased SOD, GSH-Px and CAT activity, and T-AOC. Western blot analysis and immunofluorescence staining revealed a marked decrease in caspase-3 expression and an increase in the Bcl-2/Bax ratio in the group pre-treated with matrine (30 mg/kg) as compared with the vehicle-treated group. The findings of the present study demonstrate that matrine exerts neuroprotective effects against cerebral ischemic injury and that these effects are associated with its antioxidant and anti-apoptotic properties.