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US-12616674-B2 - Anti-fibrotic NEU3 inhibitor compounds and methods of use

US12616674B2US 12616674 B2US12616674 B2US 12616674B2US-12616674-B2

Abstract

The present disclosure relates to methods of preventing or inhibiting fibrosis using small molecule sialidase inhibitors. The present disclosure also relates to methods treating obesity, liver inflammation, steatosis, and cancer. These methods can involve administering the compounds to a patent at risk of developing fibrosis inflammation, obesity, steatosis, or cancer, in a manner that inhibits NEU3.

Inventors

  • Richard H. Gomer
  • Thomas Meek
  • Tejas Karhadkar
  • Darrell Pilling

Assignees

  • THE TEXAS A&M UNIVERSITY SYSTEM

Dates

Publication Date
20260505
Application Date
20200210

Claims (11)

  1. 1 . A method of treatment of a fibrotic disorder, the method comprising administering a pharmaceutical formulation comprising a compound of formula (I) or its salt, wherein: R 1 is selected from CONH 2 , COCH 3 , and C 1-6 alkyl ester; R 2 , R 3 , R 4 , and R 5 are hydrogen; and X is nitrogen.
  2. 2 . The method of claim 1 , wherein an activity of human NEU3 in desialylating LAP is inhibited.
  3. 3 . The method of claim 1 , wherein an activity of human NEU3 in desialylating SAP is inhibited.
  4. 4 . The method of claim 2 , wherein formation or activation of fibrocytes is inhibited.
  5. 5 . The method of claim 3 , wherein formation or activation of fibrocytes is inhibited.
  6. 6 . The method of claim 1 , wherein the compound is methyl picolinate.
  7. 7 . The method of claim 1 , wherein the compound is 2-acetyl pyridine.
  8. 8 . The method of claim 1 , further comprising administering the formulation in an amount and for a time sufficient to decrease a level or activity of TGF-β1 in a human.
  9. 9 . The method of claim 1 , further comprising administering the formulation in an amount and for a time sufficient to decrease a level or activity of a sialidase in a human.
  10. 10 . The method of claim 1 , wherein the compound is picolinamide.
  11. 11 . A method of treatment of a fibrotic disorder, the method comprising: administering a pharmaceutical formulation comprising a compound of formula (I) or its salt, wherein: R 1 is selected from COOH, CONH 2 , COCH 3 , and C 1-6 alkyl ester; R 2 , R 3 , R 4 , and R 5 are hydrogen; and X is nitrogen; and administering the formulation in an amount and for a time sufficient to decrease a level or activity of a sialidase in a human.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application is a U.S. National Stage Application of International Application No. PCT/US2020/017504 filed Feb. 10, 2020, which claims priority to U.S. Provisional Application Ser. No. 62/804,262 filed Feb. 12, 2019, the contents of which are incorporated herein by reference in their entirety for all purposes. STATEMENT OF GOVERNMENT INTEREST This invention was made with government support under 1R01HL132919 and awarded by the National Institutes of Health. The government has certain rights in the invention. FIELD OF THE DISCLOSURE The present disclosure relates to anti-fibrotic, anti-cancer, anti-steatosis, anti-liver inflammation, and anti-obesity agents, and more specifically, inhibitors of the sialidase NEU3. BACKGROUND Fibrocytes are a specialized type of cell that plays an important role in the body's response to injury and in inflammation. Fibrocytes are formed when they differentiate from CD 14+ peripheral blood monocytes. Fibrocytes express markers of both hematopoietic (blood producing) cells (CD45, MHC class II, CD34) and stromal (structural tissue) cells (collagen types I and III and fibronectin). Mature fibrocytes secrete cytokines, extracellular matrix proteins, and pro-angiogenic molecules. Fibrocytes and the molecules they display extracellularly or release often result in fibrosis, which is the development of scar tissue. Instead of normal wound healing in response to an injury, fibrosis (which may result from inappropriate fibrocyte formation or activity) is harmful if it occurs to too great an extent, for too long, or in an inappropriate location. As a result, controlling the formation of fibrocytes and their activity in the body may help control harmful fibrosis, thereby avoiding or treating any resulting diseases or disorders. Obesity is the accumulation of body fat as the result of excessive food intake and/or lack of exercise. Obesity reduces life expectancy and is associated with 300,000 death annually in the U.S. Obesity also increases the likelihood of conditions such as type 2 diabetes, atherosclerosis, and high blood pressure. Transforming Growth Factor-β1 (TGF-β1) is a protein signal. Increased extracellular levels of active TGF-β1 are strongly associated with fibrosis. TGF-β1 is produced as an inactive protein complex with the latency-associated peptide (LAP), and TGF-β1 only drives fibrotic processes when it is released from the LAP complex. Sialidases are enzymes that remove sialic acid from glycoconjugates. Sialidases such as NEU1 and NEU3 are upregulated in patients with pulmonary fibrosis. NEU3 is also upregulated in some cancers, such as colon, renal, ovarian, and prostate cancers. Overexpression of NEU3 in human colon cancer cells promotes cell proliferation and adhesion, suggesting that the high levels of NEU3 observed in some tumors may potentiate the tumor. In support of the role of NEU3 in cancer, Neu3−/− knockout mice have a reduced incidence of colitis-associated colon cancer. In some cancers, high levels of NEU3 increase extracellular accumulation of the cytokine interleukin-6 (IL-6), and IL-6 is also associated with fibrosis. IL-6 also upregulates NEU3 in cultured human cells and some cancers. Serum amyloid P (SAP) is a blood protein that inhibits fibrocyte differentiation. In support of the hypothesis that sialidases potentiate fibrosis, recombinant human NEU2, NEU3, and NEU4, when added to human peripheral blood mononuclear cells (PBMC), potentiate fibrocyte differentiation and counteract the ability of human SAP to inhibit fibrocyte differentiation. Sialidases may thus potentiate fibrosis and cancer by a combination of increasing TGF-β1 and IL-6 levels. In the liver, excess calories leads to Kupffer cell (hepatic macrophages) activation which then promotes inflammation, increased hepatocyte fatty acid synthesis leading to hepatic steatosis (abnormal retention of lipids within the hepatocytes). This, in turn, can lead to fibrosis or cirrhosis. SUMMARY The present disclosure provides a method of treating a fibrotic disorder, the method comprising administering a formulation comprising a compound of formula (I): or its salt, wherein: In formula (I), R1 may be selected from hydrogen, —NO2, —CN, —COOH, —CONH2, —COCH3, C2-5acyl, C1-6alkyl ester, aryl ester, —SO3H, —SO2NH2, —SO2NH(C1-6alkyl), —SO2NH(C1-6aryl), —SO3(C1-6alkyl), —SO3(C1-6aryl), —PO3H2, —PO2H2, —PO2NH(C1-6alkyl), —PO2NH(C1-6aryl), —PO2H(C1-6alkyl), —PO2H(C1-6aryl), —PO3H(C1-6alkyl), —PO3H(C1-6aryl), and tetrazole. In formula (I), R2, R3, and R4 are independently selected from hydrogen, —NO2, —CN, —CF3, —NH2, —NH(C1-6alkyl), —N(C1-6alkyl, C1-6alkyl), —CONH2, —OH, halo, C1-6alkyl, aryl, —COOH, —NHCO(C1-6alkyl), C1-6alkyl ether, —CO(C1-6alkyl, —CO(aryl), —SO3H, —SO2NH2, —SO2NH(C1-6alkyl), —SO2NH(C1-6aryl), —SO3(C1-6alkyl), —SO3(C1-6aryl), —PO3H2, —PO2H2, —PO2NH(C1-6alkyl), —PO2NH(C1-6aryl), —PO2H(C1-6alkyl), —PO2H(C1-6aryl), —PO3H(C1-6alkyl), —PO3H(C1-6ary