An overview of the orexinergic system in different animal species.

Orexin (hypocretin), is a neuropeptide produced by a subset of neurons in the lateral hypothalamus. From the lateral hypothalamus, the orexin-containing neurons project their fibres extensively to other brain structures, and the spinal cord constituting the central orexinergic system. Generally, the term ''orexinergic system'' usually refers to the orexin peptides and their receptors, as well as to the orexin neurons and their projections to different parts of the central nervous system. The extensive networks of orexin axonal fibres and their terminals allow these neuropeptidergic neurons to exert great influence on their target regions. The hypothalamic neurons containing the orexin neuropeptides have been implicated in diverse functions, especially related to the control of a variety of homeostatic functions including feeding behaviour, arousal, wakefulness stability and energy expenditure. The broad range of functions regulated by the orexinergic system has led to its description as ''physiological integrator''. In the last two decades, the orexinergic system has been a topic of great interest to the scientific community with many reports in the public domain. From the documentations, variations exist in the neuroanatomical profile of the orexinergic neuron soma, fibres and their receptors from animal to animal. Hence, this review highlights the distinct variabilities in the morphophysiological aspects of the orexinergic system in the vertebrate animals, mammals and non-mammals, its presence in other brain-related structures, including its involvement in ageing and neurodegenerative diseases. The presence of the neuropeptide in the cerebrospinal fluid and peripheral tissues, as well as its alteration in different animal models and conditions are also reviewed.

The ameliorative effects of a phenolic derivative of Moringa oleifera leave against vanadium-induced neurotoxicity in mice.

Vanadium, a transition series metal released during some industrial activities, induces oxidative stress and lipid peroxidation. Ameliorative effect of a pure compound from the methanolic extract of Moringa oleifera leaves, code-named MIMO2, in 14-day old mice administered with vanadium (as sodium metavanadate 3 mg/kg) for 2 weeks was assessed. Results from body weight monitoring, muscular strength, and open field showed slight reduction in body weight and locomotion deficit in vanadium-exposed mice, ameliorated with MIMO2 co-administration. Degeneration of the Purkinje cell layer and neuronal death in the hippocampal CA1 region were observed in vanadium-exposed mice and both appeared significantly reduced with MIMO2 co-administration. Demyelination involving the midline of the corpus callosum, somatosensory and retrosplenial cortices was also reduced with MIMO2. Microglia activation and astrogliosis observed through immunohistochemistry were also alleviated. Immunohistochemistry for myelin, axons and oligodendrocyte lineage cells were also carried out and showed that in vanadium-treated mice brains, oligodendrocyte progenitor cells increased NG2 immunolabelling with hypertrophy and bushy, ramified appearance of their processes. MIMO2 displayed ameliorative and antioxidative effects in vanadium-induced neurotoxicity in experimental murine species. This is likely the first time MIMO2 is being used in vivo in an animal model.

Isolation of a novel compound (MIMO2) from the methanolic extract of Moringa oleifera leaves: protective effects against vanadium-induced cytotoxity.

Moringa oleifera is reported to be a miracle plant, with positive effects on practically every system in the animal body. The methanolic extract of Moringa oleifera leaves was fractionated using liquid-liquid fractionation, column chromatography and preparative high-performance liquid chromatography (HPLC). Bioassay guided fractionation using Ferric Reducing Antioxidant Power (FRAP) was used to determine the fraction with the highest antioxidative power. Chemical structure was elucidated with nuclear magnetic resonance (NMR) spectroscopy. FRAP showed that the pure compound, butyl p-hydroxyphenyl-acetate (MIMO2) exhibited an antioxidant activity higher than TEMPOL (positive control). Vanadium is a metal, which as a salt has been shown to be a neurotoxicant; and was therefore used to assess the efficacy of MIMO2 in this experiment. HT22 (immortalized mouse hippocampal) cells were used for cell culture. The Comet assay showed a statistically significant reduction (p < .05) in DNA damage when 0.25 and 0.5 µM MIMO2 as well as 0.1 and 0.2 mg of the methanolic extract of Moringa oleifera leaves (MO) were used in combination with 200 µM vanadium (sodium metavanadate). Analogously, a reduced formation of superoxide was observed using dihydroethidium (2,7-Diamino-10-ethyl-9-phenyl-9,10-dihydrophenanthridine-DHE) stain after 0.5 µM MIMO2 and 0.063 mg MO were used in combination with vanadium 100 µM. MIMO2 and MO gave a statistically significant (p < .05) protective effect against vanadium toxicity on neuronal cells. Further assays may need to be performed to assess the extent of protection that MIMO2 may offer, and also to better understand its mechanisms of action.

Skull Typology and Morphometrics of the Nigerian Local Dog (Canis lupus familiaris).

Understanding skull anatomy and morphometry is crucial to the diagnosis and treatment of some osteology disorders. This study investigated the morphometry and skull typology of the skull of the Nigerian local dog as a skull prototype for the dolichocephalic breed of dogs. A total of sixteen adult dogs (7 males, 9 females), of about 2 years were used. A total of 20 parameters were measured on each skull, and two indices (cephalic and orbital) calculated. The males had higher values for nine parameters (two of which were calculated indices), including the maximum width of the skull, length of the mandibular symphysis, height of the tympanic bulla and height of the external auditory opening, although no statistically significant difference was observed (p > 0.05). Statistically significant difference was observed in only one parameter, the length of the parietal bone (p = 0.0505), with the female value (3.775 ± 0.388 cm) being higher than the male (3.4 ± 0.179 cm). Cephalic and orbital indices (52.69 ± 4.677 % and 80.87 ± 7.218 % respectively) were higher in males (54.13 ± 1.616 % and 81.57 ± 4.295 % respectively) than in females (51.24 ± 6.434 % and 80.35 ± 9.102 % respectively), although no statistically significant difference was observed (p = 0.6905 and 0.9483 respectively). Results obtained from this study will provide baseline data on dolichocephalic skull measurements and also find application in archaeology, veterinary forensic medicine and applied anatomy.

Craniofacial morphometrics and macro-neurometrics of the fruit bat (Eidolon Helvum)

This study involved the measurement of craniofacial indices and linear neurometrics in the fruit bat, Eidolon helvum, which are found abundantly in Nigeria. The mean head weight was 38.7±2.74g, while the rima oris length, distance between medial canthi, and the height of the philtrum were 48.9±7.59 mm, 14.1±0.49 mm, 8.67±0.48 mm respectively. The brain weight and length of brain were 3.22±0.50 g and 2.79±0.18 cm respectively. The males had consistently higher values for most craniofacial and all neurometric parameters measured, while the female values were higher only in the width of the left external nares (5.08±0.55 mm in the females, and 5.0±0.39 mm in the males). Correlation studies revealed negative correlation between the weight of the animal and the weight of the brain. Data obtained from this study will serve as baseline data for craniofacial anatomy and neuro-anatomy research for the fruit bat, Eidolon helvum, and also in comparative anatomy with other breeds of bats (AU)

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Morphological and biochemical investigation into the possible neuroprotective effects of kolaviron (Garcinia kola bioflavonoid) on the brains of rats exposed to vanadium.

In this study, the morphological and biochemical susceptibility of the rat brain to vanadium, in the form of sodium metavanadate, and the comparative ameliorative effect of Garcinia kola and kolaviron (G. kola extract), was examined. Brain regions examined were the cerebrum, cerebellum, hippocampus and the olfactory bulb. We showed that vanadium administration caused cellular vacuolation, congestion, and Purkinje cell degeneration and a marked reduction in myelin tracts. Biochemical tests revealed increased lipid peroxidation induced by vanadium, which was ameliorated with the administration of G. kola and kolaviron. Vanadium administration caused an increase in thiobarbituric acid-reactive substances (TBARS) in the cerebrum and hippocampus, whereas the administration of kolaviron resulted in a reduction of the TBARS level by 65.7 and 80%, respectively, in the regions aforementioned. Also, the administration of kolaviron resulted in an increased activity of superoxide dismutase (61.24%) in all brain regions assessed, when compared with the group administered vanadium alone. Results obtained from this study led to the conclusion that kolaviron reduces vanadium-induced oxidative stress in the brain.

A rare case of left additional renal artery in a Nigerian goat.

The report of the occurrence of additional renal arteries in domestic animals is rare in the literature. We report a case of an additional renal artery in the left kidney found in a Red Sokoto goat cadaver. The additional renal artery originated from the abdominal aorta 3.80 cm cranial to the origin of the main renal artery. The additional renal artery was relatively long, being 6.30 cm from its origin to the cranial pole region of the kidney where it supplied the kidney. This to the best of our knowledge is the first report in the literature indexed in the Medline of an additional renal artery in a goat.