COMPARATIVE ANALYSIS OF PROPHYLACTIC OSTEOPROTECTIVE PROPERTY OF L-ARGININE WITH CALCIUM D3 IN EXPERIMENTALLY INDUCED HYPOESTROGENIC OSTEOPOROSIS

Раджкумар Д.С.Р.¹, Гудырев О.С.², Файтельсон А.В.³, Дубровин Г.М.⁴, Де Оливейра Родригес К.⁵, Гутемберг Сильвейра П.Э.⁶

¹Ассистент кафедры травматологии, ортопедии и военно-полевой хирургии, Курский государственный медицинский университет; ²к.м.н., доцент кафедры фармакологии и фармацевтических дисциплин, Белгородский государственный национальный исследовательский университет; ³к.м.н., доцент кафедры травматологии, ортопедии и военно-полевой хирургии, Курский государственный медицинский университет; ⁴д.м.н., профессор, заведующий кафедрой травматологии, ортопедии и военно-полевой хирургии, Курский государственный медицинский университет; ⁵студент 3 курса лечебного факультета, Курский государственный медицинский университет; ⁶студент 3 курса лечебного факультета, Курский государственный медицинский университет.

СРАВНИТЕЛЬНЫЙ АНАЛИЗ ПРОФИЛАКТИЧЕСКОГО ОСТЕОПРОТЕКТИВНОГО СВОЙСТВА L-АРГИНИНА И КАЛЬЦИЯ Д3 ПРИ ЭКСПЕРИМЕНТАЛЬНОМ ГИПОЭСТРОГЕННОМ ОСТЕОПОРОЗЕ

Аннотация

Основой развития остеопороза является дисбаланс между двумя основными процессами костного ремоделирования: костной резорбцией и образованием кости [4, 1]. Важным звеном в патогенезе остеопороза является уменьшение притока крови к кости [6], что приводит к ингибированию активности и уменьшению количества остеобластов, а также повышению активности остеокластов. Современная патогенетическая терапия этого заболевания традиционно включает препараты, которые замедляют резорбцию кости, стимулируют образование кости и препараты с множественным действием [5]. Однако увеличение частоты остеопороза и его осложнений указывает, что в настоящее время нет надежных методов лечения и профилактики этой болезни. Это демонстрирует актуальность поиска новых методов фармакологических воздействий на остеопоротические нарушения, в том числе при переломах костей скелета.

Ключевые слова: остеопороз, остеопротективное действие, L-аргинин, кальций Д3.

Rajkumar D.S.R.¹, Gudyrev O.S.², Faitelson A.V.³, Dubrovin G.M.⁴, De Oliveira Rodrigues K.⁵, Gutemberg Silveira P.H.⁶

¹Assistant department of traumatology and orthopedics and battle field surgery (Kursk state medical university),² Assistant Professor department of pharmacology and pharmaceutical discipline (Belgorod state national research university) k.m.n, ³ Assistant Professor department of traumatology and orthopedics and battle field surgery (Kursk state medical university) k.m.n, ⁴ Professor department of traumatology and orthopedics and battle field surgery (Kursk state medical university) d.m.n, ⁵ Student 3^rd year 3^rd group of medical faculty(Kursk state medical university), ⁶ Student 3^rd year 3^rd group of medical faculty(Kursk state medical university).

COMPARATIVE ANALYSIS OF PROPHYLACTIC OSTEOPROTECTIVE PROPERTY OF L-ARGININE WITH CALCIUM D3 IN EXPERIMENTALLY INDUCED HYPOESTROGENIC OSTEOPOROSIS

The purpose of the work. To do a comparative evaluation of prophylactic osteoprotective property of L-arginine with calcium D3 by company Nycomed in experimentally induced hypoestrogenic osteoporosis.

Objectives of the study. To comparatively analyse prophylactic osteoprotective property of L-arginine with calcium D3 by company Nycomed in experimentally induced hypoestrogenic osteoporosis from the results of Laser doppler flowmetry and by histomorphometry.

Abstract

The basis of development of osteoporosis is an imbalance between the two major processes of bone remodeling: bone resorption and bone formation [4, 1]. An important link in the pathogenesis of osteoporosis is to reduce the blood supply to the bone [6], which leads to inhibition of the activity and reduce the number of osteoblasts, as well as increased activity of osteoclasts. Modern pathogenetic therapy of this disease is the traditionally included drugs, which slow’s down bone resorption, stimulates bone formation and drug’s multiple action [5]. However, the increase frequency of osteoporosis and its complications indicates that there is currently no reliable methods for drug treatment and prevention of this disease. This shows the urgency of finding new methods of pharmacological effects on osteoporotic disorder in fracture of the skeleton.

Keywords: osteoporosis(OP), osteoprotective effect, L-arginine, calcium D3.

Materials and methods

In the experiment, we used female Wistar rats weighing 200-300g (number of rats - 117). All studies were performed under anesthesia (intra peritoneal injection of chloral hydrate at a dose of 300 mg / kg). Osteoporosis is modeled by a bilateral ovaryectomy [8, 3]. The animals were divided into 4 groups:

I - control (number of rats - 42)

II - after ovaryectomy (number of rats - 30);

III (number of rats - 20) - ovaryectomized rats eight weeks received therapy of L-arginine, which was administered intra gastrically at a dose of 200 mg / kg per day;

IV (number of rats - 25) – intra gastrically received drug of comparison - Calcium D3 in a dose of 85.7 mg / kg.

After 8 weeks, the level of the microcirculation in the proximal femoral metaphysisis measured . Microcirculatory parameters were recorded with a laser Doppler flow meter Biopac systems MP-100 and sensor TSD-144. After measuring intra osseous microcirculation level, without changing position of the sensor, conducted tests on endothelium-dependent vasodilation (EDVD) in response to a bolus intravenous injection of acetylcholine at a dose of 40 mg / kg [7] and endothelium non dependent vasodilatation (ENVD) in response to a bolus intravenous injection of sodium nitro prusside in a dose of 30 mg / kg [2]. Recording and processing of data carried out by program AcqKnowledge-3.8.

Osteoporosis and the effect of drugs was evaluated histo-morpho metrically  8 weeks after ovaryectomy, by the average width of the bone trabecular in the proximal femur.

Results

the level of the microcirculation in rats of the control group I was 100,5 ± 4,4 perfusion units (PU), the animals of group II - 61,5 ± 3,7 PE. In group III (L-arginine) - 98,1 ± 4,5 PE, in Group IV (Calcium D3) - 61,5 ± 2,1 PE.

In response to the systemic administration of acetylcholine and sodium nitro prusside, observed a decrease in the microcirculation with subsequent normalization of blood flow. To confirm the role of endothelial dysfunction in the development of disorders of regional microcirculation, the coefficient of endothelial dysfunction (CED) was calculated based on the LDF. In response to the systemic administration of acetylcholine and sodium nitroprusside decreased microcirculation with subsequent normalization of blood flow. CED is defined as the ratio of the area of ​​the triangle above the recovery curve of the microcirculation in response to the administration of sodium nitroprusside to the area of ​​the triangle above the recovery curve of the microcirculation in response to the administration of acetylcholine. In the group of intact animals received CED = 1,3 ± 0,2, in the group of rats with osteoporosis CED = 2,4 ± 0,2. These results indicate the formation of changes,indicating endothelial dysfunction of vessels of microcirculation of bone tissue after ovariectomy. CED treated rats (L-arginine), falls below the 1,3 ± 0,2. Calcium-D3 Nycomed does not show statistically significant effect on the coefficient of endothelial and was 2,2 ± 0,1.

Histologically there was disturbance in the average width of the trabeculae in the proximal metaphysis of the femur. In group I was 97,7 ± 1,0 µm in group II - 61,7 ± 1,2 µm, in Group III - 86,6 ± 1,4 µm, in the IV group - (with Calcium D3) -70,5 ± 2,06 µm.

Conclusion

The following conclusions are made from the rats that are Studied:

1. 8 weeks after ovaryectomy develop’s hypoestrogenic osteoporosis, in the background, in which the level of the microcirculation in the bone decreases to an average of 40%.

2. The use of L-arginine leads to a significant improvement in regional blood flow (41%). This drug is also indirectly beneficial to the processes of bone remodeling. as confirmed by histo morphometric - increase the width of trabeculae in cancellous bone of proximal femoral metaphysis by 40%;

3. Calcium D3 has no statistically significant effect on the level of regional microcirculation, although it has a positive effect on the width of bone trabeculae in the cancellous bone of the proximal metaphysis of femur by 14%.