Thiamine as a peripheral neuro-protective agent in comparison with N-acetyl cysteine in axotomized rats.

Objectives: In this study, the impact of thiamine (Thi), N-acetyl cysteine (NAC), and dexamethasone (DEX) were investigated in axotomized rats, as a model for neural injury. Materials and Methods: Sixty-five axotomized rats were divided into two different experimental approaches, the first experiments included five study groups (n=5): intrathecal Thi (Thi.it), intraperitoneal (Thi), NAC, DEX, and control. Cell survival was assessed in L5DRG in the 4th week by histological assessment. In the second study, 40 animals were engaged to assess Bcl-2, Bax, IL-6, and TNF-α expression in L4-L5DRG in the 1st and 2nd weeks after sural nerve axotomy under treatment of these agents (n=10). Results: Ghost cells were observed in morphological assessment of L5DRG sections, and following stereological analysis, the volume and neuronal cell counts significantly were improved in the NAC and Thi.it groups in the 4th week (P<0.05). Although Bcl-2 expression did not show significant differences, Bax was reduced in the Thi group (P=0.01); and the Bcl-2/Bax ratio increased in the NAC group (1st week, P<0.01). Furthermore, the IL-6 and TNF-α expression decreased in the Thi and NAC groups, on the 1st week of treatment (P≤0.05 and P<0.01). However, in the 2nd week, the IL-6 expression in both Thi and NAC groups (P<0.01), and the TNF-α expression in the DEX group (P=0.05) were significantly decreased. Conclusion: The findings may classify Thi in the category of peripheral neuroprotective agents, in combination with routine medications. Furthermore, it had strong cell survival effects as it could interfere with the destructive effects of TNF-α by increasing Bax.

A new insight into viral proteins as Immunomodulatory therapeutic agents: KSHV vOX2 a homolog of human CD200 as a potent anti-inflammatory protein.

The physiologic function of the immune system is defense against infectious microbes and internal tumour cells, Therefore, need to have precise modulatory mechanisms to maintain the body homeostasis. The mammalian cellular CD200 (OX2)/CD200R interaction is one of such modulatory mechanisms in which myeloid and lymphoid cells are regulated. CD200 and CD200R molecules are membrane proteins that their immunomodulatory effects are able to suppress inflammatory responses, particularly in the privilege sites such as CNS and eyes. Kaposi's sarcoma-associated herpesvirus (KSHV), encodes a wide variety of immunoregulatory proteins which play central roles in modulating inflammatory and anti-inflammatory responses in favour of virus dissemination. One such protein is a homologue of the, encoded by open reading frame (ORF) K14 and therefore called vOX2. Based on its gene expression profile during the KSHV life cycle, it is hypothesised that vOX2 modulates host inflammatory responses. Moreover, it seems that vOX2 involves in cell adhesion and modulates innate immunity and promotes Th2 immune responses. In this review the activities of mammalian CD200 and KSHV CD200 in cell adhesion and immune system modulation are reviewed in the context of potential therapeutic agents.