본 연구의 목적은 알츠하이머질환(Alzheimer’s disease: AD) 동물 모델을 대상으로 트레드밀 운 동(Treadmill exercise: TE)과 환경강화(environmental enrichment: EE) 처치가 인지기능, 근 기능, 및 밀 착연접 단백질 발현에 미치는 영향을 확인하는데 있다. AD 동물 모델을 제작하기 위해 aluminum chloride(AlCl3)를 90일간(40mg/kg/하루) 투여 하였으며 동시에 TE(10-12m/min, 40-60min/day) 혹은 EE에 노출시켰다. 그 결과 AlCl3 투여에 의한 인지기능 저하와 근 기능 감소가 TE와 EE에 의해 완화된 것 으로 나타났다. 또한, TE와 EE는 AD 질환에서 나타나는 β-amyloid(Aβ), alpha-synuclein 및 tumor necrosis factor-α(TNF-α) 단백질의 발현 증가를 감소시킨 것으로 나타났다. 게다가 TE와 EE는 AlCl3 투여에 의해 감소된 밀착연접 단백질(Occludin, Claudin-5 및 ZO-1)의 발현을 통계적으로 유의하게 증가시킨 것으로 나타났다. 마지막으로 Aβ 단백질과 밀착연접 단백질과의 상관분석을 실시한 결과 부적 상 관관계(Occludin: r=-0.853, p=0.001; Claudin-5 : r=-0.352, p=0.915; ZO-1 : r=-0.424, p=0.0390) 로 나타났다. 따라서 이를 종합해 보면 TE 혹은 EE 처치는 AD에 나타나는 병리학적 특징들을 일부 완화 시켜 인지기능과 근 기능을 일부 개선 시킬 수 있는 효과적인 운동 방법이라고 생각된다.

Iron is an essential nutrient for mammalian cells. Most iron absorption occurs in the duodenal epithelial cells and is regulated by hepcidin, which is produced and secreted in the liver. High hepcidin levels can cause iron deficiency anemia due to iron absorption failure. Inside the cell, iron conjugates with a porphyrin ring and is placed with an iron coordinated to heme. One of the heme-binding proteins, known as progesterone receptor membrane component 1 (Pgrmc1), is a non-canonical progesterone receptor associated with diverse molecular gene regulation. Previous studies showed that Pgrmc1 is related to iron homeostasis via hepcidin; however, these mechanisms remain to be elucidated. In the present study, to investigate the role of Pgrmc1 in mammalian iron metabolism, we introduced Pgrmc1 knockout (KO) mice and performed molecular biological analyses using qPCR and western blotting. Pgrmc1 deficiency decreased Hamp mRNA expression and hepcidin protein levels. However, Pgrmc1 deficiency failed to decrease Hamp transcript expression and hepcidin protein levels in siPGRMC1-transfected HepG2 cells and primary Pgrmc1 KO hepatocytes, respectively. PGRMC1 knockdown cells revealed low HAMP mRNA levels upon cyclic AMP (cAMP) activation, suggesting that PGRMC1 promotes HAMP mRNA transcription via cAMP activation. It has been implicated that hepatic Pgrmc1 cannot control hepcidin directly; however, the internal environment caused by the lack of Pgrmc1 may potentially cause low hepcidin levels.

This study aimed to determine the anti-obesity effect of adding Wolfiporia extensa Ginns (W) to fermented pollack skin products in an obesity-induced animal model. The experimental groups were the normal diet group (C), high-fat diet group (HF), dried pollack skin (H1), fermented pollack skin (H2), and W of 0.1 (F2-WL), 0.3 (F2-WM), and 0.5 (F2), respectively. It was confirmed that adding W to fermented pollack skin reduced blood triglycerides, total cholesterol, and LDL levels, while increasing HDL levels. Wolfiporia extensa Ginns was effective in controlling weight and improving blood lipids in a dose-dependent manner. In histological analysis, findings of fatty liver induced by a high-fat diet were improved by the addition of H2 and W. Size and density of fat globules in the epididymis were decreased. In addition, the concentration of TNF-α was increased in the high-fat diet group, but decreased by the addition of fermented pollack skin and W. In conclusion, adding fermented dried pollack skin and Wolfiporia extensa Ginns was effective for weight control and blood lipid improvement. Thus, the use of by-products in functional foods is expected to have a high value in the future.

Ischemic stroke causes severe neuronal damage. Chlorogenic acid is a phenolic substance present in fruits and coffee. It also exerts neuroprotective effects against various brain injuries. The 14-3-3 family protein perform a variety of functions including metabolism, signal transduction, cell differentiation, and apoptosis. The purpose of this study is to investigate whether chlorogenic acid regulates the expression of 14-3-3 protein in stroke animal models. Ischemic stroke was induced by middle cerebral artery occlusion (MCAO) surgery. Phosphate buffered saline (PBS) or chlorogenic acid (30 mg/kg) were intraperitoneally injected to adult male rats 2 h before MCAO surgery. Adhesive-removal test was performed 24 h after MCAO surgery and cerebral cortical tissues were collected for further study. MCAO damage caused severe neurological impairment and chlorogenic acid treatment ameliorated this disorder. Our proteomic approach showed a decrease in 14-3-3 expression in MCAO animals with PBS. The decrease in 14-3-3 expression alleviated in MCAO animal with chlorogenic acid. We confirmed changes in various 14-3-3 protein isoforms, including beta/alpha, zeta/delta, gamma, epsilon, eta, and tau through reverse transcription-PCR. These results explained that chlorogenic acid regulates the expression of 14-3-3 protein in MCAO-induced cerebral ischemia. 14-3-3 is considered to be an important protein for cell survival through binding to pro-apoptotic proteins. The maintenance of 14-3-3 levels is an important event in neuroprotection against ischemic injury. Therefore, we can demonstrate that the 14-3-3 protein contributes to the neuroprotective effect of chlorogenic acid in stroke animal models.

This study investigated the anti-obesity effects of Coriandrum sativum L. ethanol extracts in a high fat diet-induced obesity model (DIO). We confirmed the anti-obesity effects by analysing the expression of the related proteins, weight gain, dietary intake, dietary efficiency, blood biochemistry, histological analysis and western blot analysis. After oral administration of Coriandrum sativum L. ethanol extracts at concentrations of 250 and 500 mg/kg, a significant improvement in dietary efficiency, reduction in weight gain, triglycerides, total cholesterol and LDL-cholesterol in blood lipid was observed for 8 weeks. In addition, improvement in blood glucose and metabolism confirmed through glucose tolerance test was observed. Further, the concentration of alanine transaminase (ALT) in blood was significantly decreased, which improved the fatty liver caused by high-fat diet intake as confirmed by liver tissue analysis. This phenomenon was confirmed to decrease the expression of fat accumulation-related PPARγ and FAS protein in the liver tissue. Especially, it is believed that FAS, a liposynthetic enzyme, has a stronger inhibitory effect than PPARγ. Therefore, Coriandrum sativum L. ethanol extract is thought to improve obesity by reducing blood lipids levels, improving glucose metabolism and inhibiting synthesis of the fat that accumulates in the liver in high-fat diet-induced obesity animal models.

Ischemic stroke causes brain damage and neuronal cell death by depriving oxygen and nutrients and releasing excessive levels of glutamate and intracellular calcium. Epigallocatechin gallate (EGCG) is a polyphenolic compound present in green tea. It has antioxidant, anti-inflammatory, and neuroprotective effects. Hippocalcin is a calcium binding protein that regulates calcium concentration, neuronal differentiation, neuronal excitability, and neuronal cell death. In this study, we investigated whether EGCG regulates the expression of hippocalcin in neurons and astrocytes after focal cerebral ischemia. Cerebral ischemia was induced by meddle cerebral artery occlusion (MCAO). EGCG (50 mg/kg) or PBS was injected into the abdominal cavity just before MCAO surgery. Neurobehavioral tests were performed to evaluate the effect of EGCG on neurological behavioral deficits 24 h after MCAO surgery. Immunofluorescence staining was performed to evaluate the positive response to hippocalcin in the cerebral cortex after MCAO surgery. We also detected the positive reactions of neuronal nuclear protein (NeuN) and glial fibrillary acidic protein (GFAP) as markers of neuron and astrocyte, respectively. MCAO caused severe neurological impairment and EGCG treatment attenuated these impairments. MCAO damage reduced the number of NeuN-positive cells and increased the number of GFAP-positive cells. This result indicates a decrease in neurons and an increase in astrocytes. However, EGCG alleviated these changes caused by MCAO damage. MCAO reduced the number of hippocalcin-positive cells in neurons and astrocytes, and EGCG treatment attenuated these reductions. Hippocalcin exerts neuroprotective effect through regulating intracellular calcium concentration. In conclusion, EGCG regulates the expression of hippocalcin in neurons and astrocytes and has neuroprotective effects in focal cerebral ischemia.

The objective of this study was to determine the efficacy of a natural product of cherry tree (Prunus serrulata var. spontanea: PS) as a test substance for improving cytokine and ovalbumin-specific IgE using an ovalbumin-induced asthma disease model of 5-week-old male BALB/c mice. Lung tissue pathology was analyzed to confirm anti-inflammatory and asthmatic effects. As a result of examining the effect on changes in inflammatory cells in bronchoalveolar lavage fluid in an ovalbumin-induced asthma disease model by administering the PS sample, total cells, eosinophil, neutrophil, lymphocyte, and monocytes were significantly decreased. Concentrations of cytokine-based TNF-alpha and IL-4 and immunoglobulin E in serum were significantly increased in the asthma-inducing negative control group than in the normal group. However, high concentrations of PS decreased them. In histopathological examination of the lung tissue, it was confirmed that inflammatory cells infiltrated around the alveoli and bronchioles were increased in ovalbumin-induced asthma disease model. After administration of cherry tree extract, bronchiolar morphological changes such as mucosal thickening were slightly improved. From the above results, it was confirmed that extract of cherry tree significantly reduced inflammation expression and tissue damage in alveolar tissues. It was also confirmed that the cherry tree extract had an excellent efficacy in improving asthma inflammation.

Coccidiosis is caused by infection of Eimeria species and an significant parasitic disease in poultry. Various kinds of natural products have been studied to find alternative treatments for coccidiosis in chickens, but the effect of Houttuynia cordata on Eimeria infection has not been investigated. The aim of this study is to study the anticoccidial effect of H. cordata extract (HCE) in chickens after oral infection by Eimeria tenella. Anticoccidial effects of the HCE was evaluated in chickens after oral infection with E. tenella. This study was performed on threeday- old chicks (n = 30). These animals were divided into 3 groups; HCE 0.2% treated/infected (n = 10), HCE untreated/infected (n = 10) and non-infected control (n = 10). The effect of HCE on E. tenella infection was assessed by two parameters; fecal oocysts shedding and body weights gain. the chicks fed HCE significantly reduced fecal oocysts when compared to the E. tenella-infected group fed standard diets (p<0.05). Furthermore, the HCE-based diet improved weight loss due to E. tenella infection. Our data shows that HCE had significant antiprotozoal activity against E. tenella. These findings may have implications for the development of anticoccidial drugs.

The increasing prevalence of obesity is associated with various metabolic diseases such as diabetes, posing significant social and economic burdens to the society. While obesity is a complex disease with multiple factors contributing to its pathophysiology, altered glucose and lipid metabolism is evident in obese patients as well as in animal models. Abnormal metabolic regulation often leads to development of insulin resistance, a hallmark of obesity-induced type 2 diabetes. In this review, we provide a brief overview of altered lipid metabolism manifested in the obese state. In addition, two representative animal models, Mus musculus and Drosophila melanogaster, are presented with experimental approaches adopted for generation and utilization of these models. More specifically, Drosophila has been widely used for studying the core physiological phenomena across phyla for decades, mostly due to the ease of handling and sophisticated genetic manipulations with conserved cell signaling pathways of reduced redundancy. Considering a significant degree of homology in Drosophila for human disease-associated genes, it poses as a versatile in vivo platform to study the pathophysiology of various human diseases. With core metabolic pathways governing energy homeostasis generally conserved, Drosophila can be used as a model for studying molecular mechanisms underlying disease phenotypes manifested in obese and diabetic patients. In this review, we discuss representative Drosophila studies that investigated the effects of dysregulated core signaling pathways on metabolic signatures of obese animals.

목적 : Photobiomodulation 요법은 저출력 레이저 치료기술로, 당뇨망막증, 연령관련황반변성, 망막색소변성증을 포함한 퇴행성 망막질환에 대한 비침습적 치료법으로 제안되고 있다. 최근 광원으로 LED가 널리 사용되고 있으나, 망막에서 LED 기반의 Photobiomodulation에 대한 연구는 매우 부족한 실정이다. 본 연구의 목적은 670 nm LED 광원을 사용한 Photobiomodulation의 망막신경퇴화 억제효과를 조사하기 위해 시행되었다. 방법 : 670 nm LED패널, 반도체 냉각장치, 빛세기 제어기로 구성된 LED 기반의 빛 조사장치를 제작하였다. 망막신경퇴화 유도를 위해 NaIO3를 마우스에 복강주사하였다. 마우스 동공을 확대시킨 후 60 mW/cm2 출력에서 2분 동안 조사하였다. 망막의 광수용세포 손상은 바깥핵층의 두께, 광수용세포 사멸, 광수용단백질인 Rhodopsion, Opsin의 발현, 염증성 사이토카인 유전자의 발현, 뮐러세포의 반응성 신경교증 활성을 통해 분석되었다. 결과 : NaIO3에 의해 손상된 망막에 670 nm LED 빛의 조사는 망막 바깥핵층의 두께 증가, 광수용세포의 사멸 억제, 뮐러세포의 반응성 신경교증 억제, 광수용단백질의 발현 증가를 야기하였다. 결론 : 본 연구는 670 nm LED를 이용한 PBM은 망막 광수용세포의 퇴화를 손상자극 없이 효과적으로 억제할 수 있다는 것을 제시하며, 퇴행성 망막질환 치료에 새로운 전략을 제공한다.

Alzheimer’s disease (AD) is an irreversible and progressive neurodegenerative disease accompanied by aging, followed by memory impairment and cognitive decline. Although numerous attempts have been made to develop treatments for AD, most clinical trials have failed to delay or stop the progression of AD. Electroacupuncture (EA) is a complementary alternative medicine technique widely used to treat pain, inflammation, and neurodegenerative diseases. Additionally, blood-brain barrier (BBB) disruption is a known pathophysiology of neurodegenerative diseases, including AD. Moreover, amyloid beta deposition increases BBB permeability and produces inflammatory cytokines induced by glial activation. However, our previous study revealed that EA treatment at the Taegye acupoints (KI3) improves memory impairment through anti-neuroinflammation and increases glucose metabolism in 5XFAD mice. Therefore, we evaluated whether EA treatment at KI3 regulates BBB dysfunction in the prefrontal cortex of 5XFAD mice. For this study, 6.5-month-old 5XFAD mice were treated with EA stimulation at KI3 three times a week for two weeks. Western blotting, immunohistochemistry, and flow cytometry were used to evaluate the effects of EA treatment on BBB dysfunction. We found that EA stimulation attenuates BBB integrity by protecting BBB tight junction proteins (CD31, aquaporin 4, occludin, and claudin 5) in the prefrontal cortex of 5XFAD mice. In addition, EA treatment regulated inflammatory cytokines (IL-1α, IL-1β, IL-17, IL-23, IFN-ɣ, monocyte chemoattractant protein 1 (MCP-1), granulocyte-macrophage colony stimulating factors [GM-CSF], and IL-10) in the peripheral circulation of 5XFAD mice. Therefore, our data suggest that EA treatment could be a therapeutic agent for enhancing BBB dysfunction in AD.

본 연구는 PFEG(글루코실세라마이드 4.0% 함유)가 저미네랄 특수사료(HR-AD)를 섭취시킨 헤어리스 마우스에서 발생하는 피부장벽 붕괴에 대한 억제작용이 있는지를 확인하고자 하였다. 4주간의 투여를 통해 정상군(Rabo MR Stock)과 비교하여 대조군(HR-AD)에서는 경피 수분 손실량(TEWL)이 서서히 상승하여 피부장벽기능의 붕괴가 발생함과 동시에 표피 수분량 및 각층 수분량도 서서히 저하되는 것이 확인되었다. 육안적으로는 깊은 주름 형성이 확인되었으며 조직학적 소견에서는 표피의 비후와 각화 항진이 확인되었다. 그러나 PFEG를 섭취시킨 시험군에서는 대조군에서 유발되는 피부장벽기능 붕괴에 대한 억제 효과가 확인되었다. 즉, 글루코실세라마이드 0.01% 배합군 및 0.1% 배합군에서는 섭취 시작 2주일째 이후 야기되는 TEWL 상승을 완전히 억제하였다. 또한, 저하되는 표피 수분량, 각층 수분량에 대해서도 유의하게 억제하여 피부 보습 기능을 유지하고 있었다. 육안적으로도 깊은 주름 형성은 억제되었으며, 조직학적인 검토에서도 표피의 비후나 각화 항진은 확인되지 않았다. 이러한 결과는 HR- 1 마우스의 피부 세라마이드 생산 개선에 기인한 결과라고 예상된다. 즉, HR-AD 섭취에 의해 HR-1 마우스는 세라마이드를 포함한 피부 지질의 함량 및 구성에 이상이 생기고, 피부 수분량이 급격히 줄어들어 피부 보습 능력이 저하된다. 그런데 PFEG의 혼합 투여는 손상된 피부의 세라마이드 함량 및 구성을 정상과 가깝게 만들어, 대조군에서 나타나는 증상의 발현을 억제하는 것으로 판단된다. 이상의 결과로부터 PFEG의 섭취는 피부장벽기능의 손상으로 발생하는 다양한 피부 수분 손실을 억제함으로써 피부 보습 개선에 우수한 효능이 있음을 알 수 있었다. 따라서 PFEG가 피부 보습에 도움을 주는 건강기능성 원료로서 이용 가능성이 높음을 확인할 수 있다.

본 연구는 파킨슨 질환(Parkinson’s disease) 마우스 모델을 대상으로 지구성 운동과 MitoQ 섭취가 뇌의 흑질의 미토콘드리아 기능에 미치는 영향을 확인하는데 목적이 있다. 파킨슨 질환을 유도하기 위해 C57BL/6 수컷 마우스를 대상으로 복강 내 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP) 25mg/kg과 흡수를 돕기 위한 probenecid 250mg/kg을 이용하여 주 2회 5주간 총 10회 투여하였다. 실험 집단은 생리식염수를 투여하는 집단(Normal Conrol (NC), n=10), MPTP 투여집단(MPTP Control (MC), n=10), MPTP 투여 + MitoQ 투여집단(MPTP + MitoQ (MQ), n=10), MPTP 투여 + 운동집단 (MPTP + Exercise (ME), n=10), MPTP 투여 + MitoQ 투여 + 운동집단(MPTP + MitoQ + Exercise (MQE), n=10) 총 5 집단으로 구성하였으며, 운동집단은 지구성 운동을 실시하였고 MitoQ집단은 점진적으로 250μmol로 늘리면서 5주간 섭취하였다. 연구결과 Rotarod-test에서 MC 집단에 비해 처치 집단은 운동 기능 저하의 개선을 보였다. 또한 MC 집단에 비해 처치 집단은 tyrosine hydroxylase의 수준의 증가와 알파시누클린(α-synuclein) 단백질 축적을 감소시켰다. 그리고 미토콘드리아 생합성에 주요조절 인자인 PGC-1α와 항산화 효소인 Catalase 발현이 MC 집단에 비해 처치 집단에서 증가해 미토콘드리아 기능을 개선했으며, 세포사멸 조절인자인 Bcl-2의 증가와 Bax의 감소를 통해 세포사멸을 완화했다. 따라서 5주 간의 지구성 운동과 MitoQ 섭취는 파킨슨 질환에서 나타나는 병리학적 특징을 완화하고 운동기능을 향상 시키는데 효과적인 것으로 나타났다.

Probiotics improve the immune system. However, the effects of its lactic acid bacteria on atopic dermatitis relief and inflammation improvement is not fully understood. Recently, one of the probiotics, Lactobacillus helveticus HY7801 (HY7801), was found to have an anti-inflammatory effect. In this study, we investigated the effects of HY7801 on atopic dermatitis-induced animal models. After four weeks of oral administration, the group treated with HY7801 showed amelioration of the atopic dermatitis compared to the group receiving placebo. In the HY7801 treated group, the epidermal hyper-proliferation and collagen deposition were inhibited compared to the placebo group, and the secretion amount of the inflammatory factors, such as TNF-α, IL-4 were reduced. In conclusion, these results suggest that HY7801 acts as a functional probiotic via amelioration of the atopic dermatitis such as a decrease of epidermal hyper-proliferation, and collagen deposition and anti-inflammatory effects.

In vivo 측정법은 비용이 많이 들고 연구기간이 길며 동물복지 측면에서 여러 문제점이 있다. 이에 대한 대안으로 지난 수십년간 in vitro 소화율 측정법이 개발되어 왔다. 본 총설에서는 대표적인 단위동물로써 사양되고 있는 돼지의 소화기관 특징 및 소화작용에 대한 논하였다. 또한, 최근에 개발된 daisy II incubator 를 이용한 in vitro 방법을 통해 돼지에서 주요 곡류사료로 이용되고 있는 옥수수, 쌀, 소맥 및 대맥의 회장 및 전분 건물소화율을 측정하였다.

MicroRNAs (miRNAs) are a group of small non-coding RNAs consisting of 18~24 nucleotides in length. Each miRNA is expected to bind a few hundreds of putative target mRNAs, thus inhibiting their translation into protein products mostly by degradation of targets. With its biogenesis extensively deciphered, miRNAs have been implicated in a variety of biological processes, including early development and cellular metabolism. In addition, dysregulation of miRNAs and subsequent alterations in the expression of its target molecules are thought to be linked to the pathophysiology of multiple human illnesses, including cancer. To establish the miRNA-target relationships important for developing a specific disease, it is critical to validate the putative targets of each miRNA suggested by computational methods in vivo. In this review, we will first discuss oncogenic and tumor-suppressive roles of miRNAs in human cancer and introduce computational methods to predict putative targets of miRNAs. Then, the value of Drosophila melanogaster as an alternative model system will be further discussed in studying human cancer and in validating the miRNA-target relationships in vivo. Finally, we will present a possibility of applying the mammals-to-Drosophila-to-mammals approach to study the roles of miRNAs and their targets in the pathophysiology of oral cancer, an intractable type of cancer with poor prognosis and survival rate.

The early-onset familial Alzheimer's disease (EOFAD/ FAD), the less common type of Alzheimer's disease (AD) currently affects a vast number of individuals worldwide. This type is being inherited as an autosomal dominant fashion. Missense mutations on Amyloid precursor protein (APP) and Presenilins 1 and 2 (PSEN1 & PSEN2) are known as major genetic factors in FAD. Conversely, missense mutations on microtubule-associated protein tau (MAPT) are also thought to involve. Up to date, several triple-transgenic animal models with muted forms of the human APP, PSENs and MAPT have been reported. Compared to other animals, canines are more emotional and their disease signs can be easily diagnosed. This attempt was to develop a triple transgenic canine model for the AD. We have obtained the coding sequences of APP, PSEN1 and MAPT from Dana-Farber/Harvard Cancer Center DNA resource core at HMS and incorporated several common AD mutations. The transgenic construct is composed of hNSE (ENO2) promoter-driven three AD genes fused together with modified 2A sequences. It was transfected into the canine fetal fibroblasts which were then used to perform somatic cell nuclear transfer (SCNT). The viable transgenic embryos were obtained after in vitro culture and the GFP was detected. In this study, we have successfully produced viable triple transgenic canine cloned embryos using SCNT technique. These transgenic canine embryos will be further developed into canines with FAD. The transgenic canines will be a good candidate in the AD research field.

성년의 남성은 노화가 진행됨에 따라 혈중 testosterone이 감소 되면서 갱년기증상을 나타낸다. 랫드(Ratus norvegicus)는 생식 시스템이 인간과 매우 유사하여 실험 모델로 그 활용 빈도가 높은 동물이다. 본 연구에서는 남성갱년기 동물모델 확립을 위해 22주령과 50주령 랫드의 생식 기관 무게, testosterone 을 포함하는 호르몬 및 생화학적 변화에 대한 비교 연구를 진행하였다. 그 결과 22주령에 비해 50주령의 체중 및 생식기관 무게가 높게 측정 되었다. 혈중 dihydrotestosterone(DHT)는 50주령에 비해 22주령에 서 높게 측정되었다. Aspartate aminotransferasel(AST), alanine aminotransferase(ALP), total protein (TP), triglyceride(TG)와 total cholesterol(TC)은 50주령 랫드 그룹에서 유의적으로 증가되었다. 또한, 혈중 luteinizing hormone(LH)는 50주령 랫드 그룹에서 현저히 감소되었으나, follicle stimulating hormone(FSH)는 두 그룹간 차이를 나타내지 않았다. 본 연구의 결과들을 종합할 때 22주령과 50주령 랫드의 비교 실험은 남성갱년기 동물모델 시스템으로 적용 가능할 것으로 판단되며 보다 확고한 남성갱년기 전용 동물모델 시스템 확립을 위해서는 생육기간에 따른 다양한 인자들에 대한 지속적인 연구가 진행되어야 할 것으로 판단된다.