Hyperglycaemia exacerbates choroidal neovascularisation in mice via the oxidative stress-induced activation of STAT3 signalling in RPE cells.

Choroidal neovascularisation (CNV) that occurs as a result of age-related macular degeneration (AMD) causes severe vision loss among elderly patients. The relationship between diabetes and CNV remains controversial. However, oxidative stress plays a critical role in the pathogenesis of both AMD and diabetes. In the present study, we investigated the influence of diabetes on experimentally induced CNV and on the underlying molecular mechanisms of CNV. CNV was induced via photocoagulation in the ocular fundi of mice with streptozotocin-induced diabetes. The effect of diabetes on the severity of CNV was measured. An immunofluorescence technique was used to determine the levels of oxidative DNA damage by anti-8-hydroxy-2-deoxyguanosine (8-OHdG) antibody, the protein expression of phosphorylated signal transducer and activator of transcription 3 (p-STAT3) and vascular endothelial growth factor (VEGF), in mice with CNV. The production of reactive oxygen species (ROS) in retinal pigment epithelial (RPE) cells that had been cultured under high glucose was quantitated using the 2',7'-dichlorofluorescein diacetate (DCFH-DA) method. p-STAT3 expression was examined using Western blot analysis. RT-PCR and ELISA processes were used to detect VEGF expression. Hyperglycaemia exacerbated the development of CNV in mice. Oxidative stress levels and the expression of p-STAT3 and VEGF were highly elevated both in mice and in cultured RPE cells. Treatment with the antioxidant compound N-acetyl-cysteine (NAC) rescued the severity of CNV in diabetic mice. NAC also inhibited the overexpression of p-STAT3 and VEGF in CNV and in RPE cells. The JAK-2/STAT3 pathway inhibitor AG490 blocked VEGF expression but had no effect on the production of ROS in vitro. These results suggest that hyperglycaemia promotes the development of CNV by inducing oxidative stress, which in turn activates STAT3 signalling in RPE cells. Antioxidant supplementation helped attenuate the development of CNV. Thus, our results reveal a potential strategy for the treatment and prevention of diseases involving CNV.

[Study on inter-individual variability of cerebral response to acupuncture with fMRI].

OBJECTIVE: Effects of inter-individual variability on fMRI of acupuncture were observed and the possible influencing factors were further analyzed. METHODS: Twenty-six healthy volunteers were selected. And acupuncture was applied at Zusanli (ST 36) on the left side with even manipulation. The same experimental designation and data collecting reference were adopted to collect functional data. Then, the same data processing method was applied for analyzing individual data. Data which did not confirm with data analyzing qualification were rejected. The 26 individual data which met the requirement were taken randomly for 5 times according to the principle of random group division. Five groups named with A, B, C, D and E were thus generated with 11 samples in each. Images were processed with the AFNI software for every group, and the activated brain areas were revealed. RESULTS: Activated areas in the brain were observed in all the 5 groups, and the results vary a lot among different groups. Decreased signals of activated brain areas were observed in group C, while increased signals were seen in group D. Partial increasing and partial decreasing signals appeared in the other 3 groups. Compared with other groups, group D demonstrated totally different activated areas. The rate of difference among different groups is 46.7%-100.0%, and most of the differences were over half of the activated areas. CONCLUSION: Under the pre-requisites of strict control of experimental designation, acupuncture method, data collecting and processing, great differences have been found in the activated areas of the brain. It indicates that obvious individual differences existes in the activated areas of the brain with acupuncture. And the difference may greatly influence the researching result of fMRI as well as conclusions of those results.

[Study on the relative specificity of the heart and lung meridians in brain with fMRI].

OBJECTIVE: To study the central modulation mechanism on the relative specificity of the Heart and Lung Meridians and to provide the experimental evidence for deeply study on correlation between meridian-viscera and brain. METHODS: Ten healthy students in Anhui College of TCM were chosen and a modified block design was adopted. After 32 time points of resting and 32 of rotation needling, then 48 of resting and 32 stimulating, and 16 resting time points, functional imagings were collected at last. All the process would last for 10 min 44 sec. Acupuncture work was finished by one acupuncturist with extensive experience by acupuncture at the left Shenmen (HT 7) or Taiyuan (LU 8) with the disposable sterile stainless steel needle, and uniform reinforcing-reducing method was used with frequency of 1 Hz and depth of 1.0 cm. After the experiment, the sensation of acupuncture and the other feeling or psychic process were inquired and recorded detailedly. These data were analyzed by AFNI software. RESULTS: Acupuncture at Taiyuan (LU 8) could excite the contralateral frontal lobe, apical lobe, cerebral ganglion, VI, VIII areas and inferior semilunar lobule of cerebellum, and restrain bilateral callosal gyrus and homolateral gyrus rectus. Acupuncture at Shenmen (HT 7) could excite the contralateral IV-VIII areas of cerebellum, and homolateral VI, VII areas of cerebellum, and restrain parts of homolateral apical lobe. CONCLUSION: Acupuncture at Shenmen (HT 7) of the Heart Meridian and Taiyuan (LU 8) of the Lung Meridian can excite or restrain different brain areas, indicating that there are relatively specific corresponding brain areas for the Heart Meridian and Lung Meridian.