Bone density, fractures and the associated factors in iranian children and adolescent with Osteogenesis Imperfecta

Backround

Osteogenesis imperfecta(OI) is a frequent bone fragility disorder in children. The purpose of this study was to assess the BMD and Vitamin D level in children with OI in southern Iran.

Method

This case-control study was conducted on 23 children, clinically diagnosed as osteogenesis imperfecta and 23 age- and gender-matched healthy controls. Demographic and anthropometric data, biochemical parameters, puberty, sun exposure and physical activity were assessed. Bone mineral density (BMD) was measured by Dual-energy X-ray absorptiometry (DXA). Data analysis was done by SPSS22.

Results

Forty-three point four percent of OI patients and fifty-six point five percent of control group had vitamin D deficiency (P = 0.376). Thirteen OI patients (56%) had low bone mass for chronological age in lumbar area (P < 0.001). Fracture episodes during treatment was significantly influenced by time of Pamidronate start, courses of Pamidronate injection, puberty and sun exposure (P values = 0.015, 0.030, 0.044 and 0.032, respectively). Fracture episodes during treatment had significantly increased in patients who had received Pamidronate more than 3 years compared with those received less than 3 years(P values = 0.047).

Conclusions

This study showed that vitamin D deficiency is prevalent amongst OI children in southern Iran. More than half of the OI children had low bone mass for chronological age in lumbar area, despite receiving bisphosphonate therapy. The present results revealed that early initiation of Pamidronate and number of Pamidronate courses are associated with lower fracture rate. However, treatment period more than 3 years can have adverse effect on fracture rates.

Effect of prolactin and estrogen on the serum level of 1,25-dihydroxy vitamin D and FGF23 in female rats

INTRODUCTION

Estrogen and prolactin affect vitamin D metabolism. In conditions such as pregnancy and lactation, their interaction in regulating vitamin D metabolism and circulating FGF23 is not clearly defined. The aim of this study is to investigate this interaction in female rats.

METHOD

This study was performed on 50 female adult rats, which were divided into five groups of Sham, ovariectomized rats (O), and three groups of ovariectomized rats were indicated with prolactin alone (OP), estradiol alone (OE), and a combination of estradiol and prolactin (OEP). Serum levels of 25(OH)D, 1,25(OH)2D3, FGF23, PTH, vitamin D-binding protein, calcium, and phosphorous were evaluated.

RESULTS

Serum 1,25(OH)2D3 and PTH in OE were higher than the O group (P < 0.001 and P = 0.003, respectively). Serum FGF23 in the OE group was lower than the O group (P = 0.016). Serum 1,25(OH)2D3 increased in OP compared to the O group (P < 0.001) and OE group (P < 0.001). Serum FGF23 in OP was lower than the O group (P = 0.04). Furthermore, combining estradiol and prolactin showed no extra effect on increasing serum 1,25(OH)2D3. Serum 1,25(OH)2D3 was positively correlated with serum prolactin levels (r = 0.318, P = 0.017) in all five groups.

CONCLUSION

It is suggested that estradiol could increase 1,25(OH)2D3 by elevating PTH and decreasing serum FGF23; however, prolactin was able to increase 1,25(OH)2D3 by lowering serum FGF23. Moreover, prolactin was shown to be more potent in augmenting serum 1,25(OH)2D3 than estrogen itself, which is important in maternal and fetal calcium supply during late pregnancy and lactation.

Interaction between serum FGF-23 and PTH in renal phosphate excretion, a case-control study in hypoparathyroid patients

BACKGROUND

phosphate homeostasis is mediated through complex counter regulatory feed-back balance between parathyroid hormone, FGF-23 and 1,25(OH)2D. Both parathyroid hormone and FGF-23 regulate proximal tubular phosphate excretion through signaling on sodium- phosphate cotransporters II_a and II_c. However, the interaction between these hormones on phosphate excretion is not clearly understood. We performed the present study to evaluate whether the existence of sufficient parathyroid hormone is necessary for full phosphaturic function of FGF-23 or not.

METHODS

In this case-control study, 19 patients with hypoparathyroidism and their age- and gender-matched normal population were enrolled. Serum calcium, phosphate, alkaline phosphatase,parathyroid hormone, FGF-23, 25(OH)D, 1,25(OH)2D and Fractional excretion of phosphorous were assessed and compared between the two groups, using SPSS software.

RESULTS

The mean serum calcium and parathyroid hormone level was significantly lower in hypoparathyroid patients in comparison with the control group (P < 0.001 and P < 0.001, respectively). We found high serum level of phosphate and FGF-23 in hypoparathyroid patients compared to the control group (P < 0.001 and P < 0.001, respectively). However, there was no significant difference in Fractional excretion of phosphorous or 1,25OH2D level between the two groups. There was a positive correlation between serum FGF-23 and Fractional excretion of phosphorous just in the normal individuals (P < 0.001, r = 0.79).

CONCLUSIONS

Although the FGF-23 is a main regulator of urinary phosphate excretion but the existence of sufficient parathyroid hormone is necessary for the full phosphaturic effect of FGF-23.

The effect of testosterone itself and in combination with letrozole on bone mineral density in male rats

Testosterone is an essential hormone to maintain bone integrity; however, the effect of aromatase enzyme in androgen-induced bone maintenance remains somewhat unclear. The present study evaluated the effect of testosterone itself and combined with letrozole, an aromatase inhibitor, on bone mineral density of male rats. Total of 48 male rats were divided into 4 equal groups (n = 12/group); sham group, O: orchiectomy, O + T: orchiectomized rats treated with testosterone, O + T + L: orchiectomized rats treated with combination of testosterone and letrozole. Bone density (BMD), bone markers, and vitamin D metabolism parameters were checked in all groups before and after the study. There was no significant difference in baseline values of these parameters, but at the end of the study there was a significant decrease in delta BMD at both lumbar and femor in orchiectomized rats in comparison with the sham group (p < 0.001, p < 0.001, respectively). Both testosterone and its combination with letrozole increased lumbar and femoral BMD of orchiectomized rats, with a higher increase in lumbar BMD in O + T group. CTX were higher in O group rats. The present study showed a major role for testosterone on BMD maintenance in male rats. However, testosterone has a potent effect on lumbar BMD, by the aromatization to estradiol.

The effect of prolactin itself and in combination with estrogen on bone mineral density in female rats

Estrogen deficiency induced by hyperprolactinemia can reduce bone mineral density. Hyperprolactinemia through other mechanisms other than estrogen deficiency, with direct effect on the bone might cause bone loss in women. The present study evaluated the effect of prolactin itself and in combination with estrogen on bone mineral density of female rats. This study was performed on 50 adult female rats divided into five groups; included (a) Sham, (b) Ovariectomized rats; and (c-e) included ovariectomized rats were given prolactin alone, prolactin + estradiol and estradiol, respectively. Bone mineral density (BMD) and vitamin D metabolism parameters were checked in all groups before and after the study. There was no significant difference in baseline values of these parameters. Estradiol could increase 1,25(OH)2D3 and PTH levels and decrease serum ALP level. In addition, Prolactin could increase serum 1,25(OH)2D3 and ALP levels and decrease tibia BMD significantly without any change in PTH level. Combination of estradiol and prolactin could increase serum 1,25(OH)2D3 and PTH and tibia BMD compared with OVX group. Combination of estradiol and prolactin could significantly increase tibia BMD, in ovariectomized rats. We hypothesized that this combination could improve bone loss secondary to hyperprolactinemia by elevated PTH.

Bone mineral density loss in ambulatory children with epilepsy in spite of using supplemental vitamin D in Southern Iran: a case-control study

Epilepsy might have adverse effect on bone density due to underlying disease, drugs, vitamin D deficiency, immobilization and malnutrition. We investigated the bone mineral density in ambulatory vitamin-D supplemented children with epilepsy. This case-control study was conducted on 90 epileptic children aged 11.4 ± 3.3 years, and age and gender matched controls in pediatric neurology clinics of Shiraz, in Southern Iran, 2016. Anthropometric measurements, puberty, sun exposure, physical activity and biochemical variables were assessed. Bone mineral density was evaluated by dual-energy X-ray absorptiometry method. Data were analyzed by SPSS.v21. Prevalence of low bone mass in femur was more in patients (27%) than the controls (9%) (P value = 0.002). Age, weight Z score and height Z score were the most significant associated factors on lumbar BMD, BMAD, and femur BMD. Seizure duration and how it responded to anticonvulsants were the most associated factors with both lumbar and femur bone density. Sodium valproate and carbomazepin usage had negative association with lumbar Z score (beta = - 0.216, P = 0.017 and beta = - 0.336, P = 0.027, respectively). We hypothesized that epilepsy per se could affect bone density by an unknown pathophysiology, which was independent from vitamin D deficiency, effects of anticonvulsant and physical activity.

Investigating the effect of testosterone by itself and in combination with letrozole on 1,25-dihydroxy vitamin D and FGF23 in male rats

BACKGROUND

Testosterone deficiency might be associated with vitamin D levels in hypogonadal men, but it is not clear whether testosterone can affect vitamin D and fibroblast growth factor-23 (FGF23), either directly or indirectly via aromatization to estradiol. We aimed to investigate the role of testosterone on vitamin D metabolism and serum FGF23 in male rats.

METHODS

A total of 48 male rats were divided into 4 equal groups: sham; O, orchiectomy; O + T, orchiectomized rats treated with testosterone; and O + T + L, orchiectomized rats treated with combination of testosterone and letrozole. We compare the vitamin D metabolism biochemical parameters in these four groups, before and after the study.

RESULTS

We detected a significant reduction in 25-hydroxyvitamin D (25(OH)D), vitamin D binding protein (DBP), FGF23, and 1,25-dihydroxyvitamin D (1,25(OH)2D) serum level in O group compared to sham group (p = 0.004, p = 0.009, p < 0.001 and p < 0.001, respectively), and a significant increase in serum phosphorus, parathyroid hormone (PTH), and alkaline phosphatase (ALP) levels in orchiectomized rats in comparison to sham group (p < 0.001, p = 0.022, and p = 0.006, respectively). However, these changes were corrected by testosterone replacement in O + T and O + T + L groups. In addition, we found that DBP and 1,25(OH)2D serum levels were significantly higher in O + T group in comparison to O + T + L group (p = 0.030 and p = 0.026, respectively).

CONCLUSIONS

Testosterone plays a significant role on regulating 25(OH)D, DBP, FGF23, phosphate (Phos), PTH, and 1,25(OH)2D serum levels in male rats. Also, testosterone has a potent effect on 1,25(OH)2D and DBP by its conversion to estradiol.

Effect of Cholecalciferol therapy on serum FGF23 in vitamin D deficient patients: a randomized clinical trial

INTRODUCTION

Fibroblast growth factor-23 plays an important role in regulating systemic phosphate homeostasis, and vitamin D metabolism. However, the effect of Cholecalciferol therapy on FGF₂₃ serum level in patients with vitamin D deficiency has not been studied, yet.

MATERIALS AND METHODS

This is a double-blind, randomized clinical trial on 119 vitamin D deficient patients in 2016. Biochemical variables of treatment and placebo groups were analyzed after 12 weeks of 50,000 IU of Cholecalciferol vs. placebo therapy once a week, by SPSS18.

RESULTS

After Cholecalciferol therapy, delta of serum PTH in treatment group was less than the controls (P < 0.001). However, delta values of serum 25(OH)D₃, 1,25(OH)₂D₃ and FGF₂₃ in vitamin D treated group were more than the placebo-treated ones (P < 0.001, P = 0.002, and P = 0.04, respectively). Moreover, FGF₂₃ serum level in treatment group was associated with serum calcium (P = 0.005, r = -0.256), and serum 1,25(OH)₂D₃ (P < 0.001, r = 0.529).

CONCLUSIONS

We propose that in these patients 1,25(OH)₂D₃ has a positive association with serum FGF₂₃, and hypostasized that serum calcium might be a down regulator of serum FGF₂₃.

Effects of essential oil of Satureja khuzestanica on the oxidative stress in experimental hyperthyroid male rat

This work analyzes the effects of Satureja khuzestanica essential oil (SKEO) on the thyroid and antioxidant system, assessed by measuring levels of tri-iodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), malondialdehyde (MDA), reduced glutathione (GSH), and glutathione peroxidase (GPx) activity. Forty adult male Sprague Dawley rats (225 ± 25 g) were divided into five equal groups: one control and four hyperthyroid groups that received placebo, 200 mg kg(-1) body weight of vitamin (Vit.) E, 225 mg kg(-1) body weight of SKEO, 200 and 225 mg kg(-1) body weight of Vit. E and SKEO together, respectively. Hyperthyroidism was induced by administering of L-thyroxin in drinking water. After 30 days of L-thyroxin consumption, serum T3 and T4 levels, TSH, and oxidative stress indices were determined. Significant increase in serum T3, T4 and MDA concentrations with a simultaneous significant decrease in TSH, GSH level and GPx activity were observed in hyperthyroid group (p <0.05). In the treatment groups, SKEO and/or Vit. E can compensate serum MDA elevation and GPx activity reduction. Only, SKEO + Vit. E could compensate the decline of GSH levels in response to hyperthyroidism. Supplementation of SKEO, plus Vit. E as antioxidants is useful in attenuating lipid peroxidation and may potentially benefit hyperthyroid patients.

Hepatoprotective effect of satureja khuzestanica essential oil and vitamin e in experimental hyperthyroid rats: evidence for role of antioxidant effect

BACKGROUND

Hyperthyroidism is associated with liver oxidative stress causing liver dysfunction in many hyperthyroid patients. The hepatoprotective effect of Satureja Khuzestanica Essential Oil (SKEO), as herbal origin antioxidant and anti-inflammatory agent on the hyperthyroidism induced hepatotoxicity and oxidative stress is investigated.

METHODS

Adult male sprague dawley rats were divided into categories of; control (group C), hyperthyroid (group H), hyperthyroid with olive oil (group H+O), hyperthyroid with vitamin E (group H+E), hyperthyroid with SKEO (group H+S), combination of hyperthyroid with vitamin E and SKEO (group H+S+E). Hepatoprotective and antioxidant properties of SKEO with or without vitamin E in hyperthyroid rats were then investigated.

RESULTS

Serum Aspartate Transaminase (AST) and Alanine Transaminase (ALT) activities reduced significantly in H+O, H+E, H+S and H+S+E groups in comparison with hyperthyroid rats. Enzymes activities returned to normal in H+S+E group. Hepatic Malondialdehyde (MDA) was reduced in H+E, H+S and H+S+E groups in comparison with hyperthyroid rats. The most significant MDA reduction was in the H+S+E group. Glutathione Peroxidase (GPx) and Glutathione Reductase (GR) activities increased in H+E, H+S and H+S+E groups in comparison with group H. The largest increment in GPx and GR activities were in the H+S+E group. Glutathione level did not change in any group in comparison with the control group.

CONCLUSION

Administration of SKEO has hepatoprotective effect in hyperthyroid rats and is more effective when used in combination with vitamin E.

Short-course treatment in neurobrucellosis: a study in Iran

Neurobrucellosis is a rare neurological complication of brucellosis. This report describes 19 patients of neurobrucellosis and they accounted for 8% of all cases of brucellosis admitted to Shiraz University Hospitals over a period of eight years. Headache, fever, fatigue, drowsiness and neck stiffness were the common clinical features. Cerebrospinal fluid (CSF) showed pleocytosis in 100%, elevated protein levels in 89% and low glucose level in 47% of the patients. All the patients improved with specific antibiotic treatment. Of the 19 patients, 10 (52.5%) patients received treatment for 8 to 28 weeks. Duration of antibiotic treatment was: 8-14 weeks in 8 (42%) patients; 24-28 weeks in 2 (10.5%) patients; 6 months in 7 (37%) patients; 12 months in 1 (5.3%) patient; and 18 months in 1 (5.3%) patient. Clinicians in endemic areas should consider the likelihood of neurobrucellosis in patients with unexplained neurological and psychiatric symptoms.