Metabolic Drug Efficacy Testing

GemPharmatech has independently developed a series of metabolic disease models for conditions such as obesity, diabetes, non-alcoholic steatohepatitis (NASH), hyperlipidemia, gout/hyperuricemia, arthritis, and inflammation. Read more about these models here.
 
We provide a range of drug efficacy testing services to complement these metabolic mouse models.
 

Monogenic Obesity and Diet Induced Obesity (DIO)

B6-Lep KO mice and B6-Alms1 Del mice are monogenic obese models. Homozygous mutant mice show early onset obesity starting from about 4 weeks of age. Body weight gain continues well beyond adulthood, leading to more than twice the body weight of an adult wildtype mouse. Diet-induced obese mice, on the other hand are wildtype C57BL/6J mice fed on a high fat diet (HFD) or high fat high sucrose diet (HFHSD) for an extended period of time. They accumulate more weight than a typical wildtype mouse that is fed with control diet. They provide a mouse model for the most commonly diagnosed type of human obesity.
 
When used for preclinical efficacy and safety evaluation, obese mice are randomized to receive investigational drugs or control. The total testing course is typically 3-8 weeks for genetic obese models and 12-20 weeks for DIO models. Tested items include:
  • Body weight
  • Food intake
  • Postprandial and fasting blood glucose
  • Glycated hemoglobin (HbA1c)
  • Glucose Tolerance Test (GTT) and Insulin Tolerance Test (ITT)
  • Blood biochemistry (e.g., ALT, AST, TG, CHOL, HDL-C, LDL-C)
  • Plasma insulin
  • Body composition
  • Physiological cage testing (urine and feces collection)
  • Metabolic cage testing (CO2 production, O2 consumption, heat production, RER, and voluntary activity)
  • Tissue and organ collection
  • Histopathological analysis (e.g., H&E, Sirius Red, Masson, Oil Red, IHC staining)
  • Gene expression analysis

Monogenic Models and Induced Models for Type II Diabetes

Leptin-receptor-deficient mice (BKS-Lepr KO mice) carry a single base-pair mutation in the leptin receptor gene and exhibit symptoms of Type II diabetes (T2D), such as hyperglycemia and hyperinsulinemia starting at 4 weeks of age. In the absence of genetic abnormalities, high fat diet treatment combined with low-dose streptozotocin (STZ) can induce the symptoms of T2D in C57BL/6 wildtype mice. These models are suitable for preclinical efficacy and safety testing of anti-T2D drugs.
 
Studies typically involve 5-8 groups of mice with 10-12 mice per group. The groups include a negative control, a positive drug control, a vehicle control, test drug groups at high, medium, and low doses. The typical test duration is 8-12 weeks. Tested items include:
  • Body weight
  • Food intake
  • Plasma glucose
  • HbA1c
  • GTT and ITT
  • Serum insulin
  • Body fat ratio
  • Metabolic cage test
  • Plasma lipids
  • Chemokine and cytokine assessment

Liver Diseases

Liver Fibrosis

Carbon tetrachloride (CCl4) is the most widely used toxin to induce liver fibrosis. The CCl4-induced liver fibrosis mouse model is suitable to test the effect of anti-fibrosis drugs. Multiple mouse strains may be used. A typical test period is 8-10 weeks and the test items include:
  • Fibrosis scoring
  • Fibrosis marker assessment (e.g., TGFβ1& COL1A1& TIMP1& ACTA2)
  • Histopathological analysis (H&E staining, Sirius Red staining)

Non-Alcoholic SteatoHepatitis (NASH)

Non-alcoholic fatty liver disease (NAFLD) is a condition in which excess fat accumulates in the liver of patients that do not have a history of alcoholism. Non-alcoholic steatohepatitis (NASH) is a more severe form of NAFLD, which manifests as liver steatosis and is accompanied by intralobular inflammation, hepatocellular ballooning, and fibrosis. Preclinical study using animal models is indispensable for the development of novel anti-NASH drugs. GemPharmatech provides a series of genetic, chemical and diet-induced NASH models for drug efficacy and safety testing, for example BKS-Lepr KO and B6-Alms1 Del mice with Western diet treatment.
 
The test period is typically 8-10 weeks. Tested items include:
  • Body weight
  • Food intake
  • Plasma glucose and lipids
  • HbA1c
  • GTT
  • Fibrosis and NAFLD scoring
  • Fibrosis marker assessment
  • Histological analysis

Atherosclerosis

Atherosclerosis is a chronic disease caused by the deposition of fats, cholesterol, calcium, and other substances in the endothelium of arteries, which leads to loss of arterial elasticity due to vessel thickening and stiffening. The thick plaques which occlude an artery can severely decrease blood flow to downstream vascular tissue thereby causing detrimental tissue damage. To provide a preclinical testing platform for atherosclerosis, GemPharmatech generated ApoE and Ldlr knockout mice on the C57BL/6 genetic background using CRISPR/Cas9 gene editing technology, as both genes play important roles in regulating lipid metabolism and plasma cholesterol. We subject both mutant strains to Western diet treatment to promote the incidence and development of atherosclerosis, and have established a testing platform with optimized use of either model.
 
Testing typically involves 3-8 groups with 5-10 mice per group. The typical test period is about 8 weeks. Tested items include:
  • Body weight
  • Blood lipids
  • Pathological tests (e.g., immunohistochemistry, special staining)
  • Protein immunization
  • qRT-PCR

Hyperlipidemia

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a known secretory factor that negatively regulates the expression level of LDLR on the cell membrane. Studies on the human PCSK9 gene have shown that PCSK9 gain-of-function mutations are related to familial hyperlipidemia, so PCSK9 is a target for the development of anti-hyperlipidemia drugs. GemPharmatech’s B6-hPCSk9 mice develop hyperlipidemia when fed a high cholesterol diet.
 
Drug efficacy testing is performed with B6-hPCSk9 fed a Western diet for 5-6 weeks prior to dosing with investigational product or control. Testing time is typically 8-10 weeks with 3-5 groups each containing 8-10 mice.
 

Gout and Hyperuricemia

Injecting urate into local tissues or joints of mice leads to the deposition of uric acid crystals in tissues, which effectively replicates acute gout symptoms in humans. This model has been used for the preclinical study of gout and anti-inflammatory drugs. Testing is typically performed using 6 groups of C57BL/6J mice, 10-12 mice per group. The typical test period is 2 weeks and test items include:
  • Observation of the degree of swelling of mouse feet
  • Detection of inflammatory biomarkers in blood
  • Histopathological analysis
  • Gene expression analysis (qRT-PCR and WB)

Arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disorder with systemic inflammation that primarily affects joints, causing painful swelling of the joints which can later progress to the destruction of the articular cartilage and ankylosis of the joints. Its pathogenesis is still not fully understood. The Type II Collagen-Induced Arthritis (CIA) mouse model has been widely used as a tool to study the pathogenic process of RA. GemPharmatech conducts contract-based studies in CIA mice to determine an investigational product’s efficacy and safety. Testing is done with 3 groups of DBA/1 or DBA-hIL17A mice, 5-10 mice per group. The test period is typically 8-12 weeks. Tested items include:
  • Paw rating according to the severity of symptoms
  • Inflammatory biomarker detection
  • Histopathological analysis
  • qRT-PCR analysis

Inflammation

Intestinal Inflammation and DSS-Induced Colitis

Human patients of inflammatory bowel disease (IBD), characterized by chronic inflammation of the gastrointestinal tract, have an increased risk of developing colorectal cancer (CRC). Dextran sodium sulfate (DSS)-induced IBD model is advantageous over other chemically induced models due to its rapidity, stability, and reproducibility. In addition, colorectal cancer can be induced by the combination of DSS with Azoxymethane (AOM). Such models have been widely used for evaluating new drugs treating intestinal inflammation, IBD and CRC.
 
Both wildtype mice (such as C57BL/6J) and mutant mice with desired genetic modifications can be used to establish these models with the appropriate chemical insult. The testing period is typically 3-15 weeks with 3-8 groups of 5-10 mice per group. Tested items include:
  • Inflammation rating
  • Inflammatory biomarkers detection
  • Histopathological analysis
  • IHC and IF
  • qRT-PCR
Preclinical Services | Metabolic Drug Efficacy Testing — GemPharmatech