Table 2: Possible factors influencing intestinal cholesterol absorption.

FactorsInfluencingResearch methodReferences

(A) Dietary Factors
↑  Cholesterol(-)Mouse feeding studiesDuan 2004 [64]
Fat
 ↑  Stearic AcidRat feeding studiesKelley 1978 [65];
Vahouny 1988 [66]
 ↑  MUFAsAfrican green monkey feeding studiesJohnson 1985 [67]
 ↑  ω-3 PUFAsAfrican green monkey feeding studies
Caco-2 cells
Johnson 1985 [67] 
Fang 2018 [44]
 ↑  Fish OilRat feeding studiesChen 1987 [68]
↑  CelluloseHamster feeding studiesTurley 1994 [69]
↑  PhytosterolsHuman intervention (see table in reference)Nguyen 1999 [70]
↑  Soluble FibersRat and hamster feeding studiesFeldman 1979 [71]; Schneider 2000 [72]
↑  EzetimibeHuman and hamster feeding studiesRosenblum 1998 [73]; Davis 2004 [53]
↑   SphingomyelinMouse feeding studiesEckhardt 2002 [74]
(B) Bile acid factor
↓  Bile acid outputCyp7a1(-/-) miceSchwarz 2001 [55]
↓  Bile acid/salt pool sizeCyp7a1(-/-) miceSchwarz 2001 [55]
↓  Bile acid phospholipid outputAbcb4(-/-) miceWang 1998 [54]
↑  Bile acid cholesterol outputVarious mouse strainsWang 2001 [60]
↑  Cholesterol content in bile saltsVarious mouse strainsWang 2001 [60]
↑  Hydrophobic bile saltMouse feeding studiesWang 2003 [57]
↑  Hydrophilic bile saltMouse feeding studiesWang 2003 [57]
(C) Genetic factors
↓  ACAT2Inhibitor in mice
Acat2(-/-) mice
Buhman 2000 [75];
Clark 1984 [76]
↓  HMG-CoA RInhibitor in human and miceHajri 1995 [77];
Vanhanen 1992 [78]
↓  ABCA1↓  
 ↑
Abca1 (-/-) miceMcNeish 2000 [79];
Drobnik 2001 [80]
↓  ABCG5 and ABCG8Abcg5/g8(-/-)miceYu 2002 [81]
↓  NPC1L1Npc1/1(-/-) mice
Inhibitor in mice
Altmann 2004 [82];
Davis 2004 [53]
↓  SR-BI(-)  Sr-b1 (-/-) miceMardones 2001[83];
↑  SR-BI   ↑   Overexpression in CHO cellsAltmann 2002 [84];
↑  SR-BIHepatic overexpression in miceSehayek 1998 [85]
↓  Caveolin1(-)Cav1 (-/-) miceValasek 2005 [86]
↓  MTPInhibitor in humanSamaha 2008 [87];
Cuchel 2007 [88]
↓  APO-B48ApoB48 (-/-) mice
Apo-B100-only mice
Young 1995 [89];
Wang 2005 [90]
↑  LXRsAgonist in humanRepa 2000 [91]
↑  FXRAgonist in humanRepa 2000 [91]
↑  RXRαAgonist in miceRepa 2000 [91]
↑  PPARαPparα (-/-) and agonist in miceKnight 2003 [92]
↑  PPARδAgonist in miceVan Der Veen 2005 [92]
(D) Intestinal lumen factor
↑  Small intestine transit timeCck-1 receptor (-/-) miceWang 2004 [59]
↑  Gastric emptying timeVarious of mouse strainsKirby 2004 [93]
↓  MUC1Muc1 (-/-) miceWang 2004 [59]
↓  CEL(-)   
 ↓
Cel (-/-) mice
Cel (-/-) mice
Kirby 2002 [94]
Weng 1999 [95]
↓  PTLPtl (-/-) miceHuggins 2003 [96]

Table 2 is modified from Wang 2005 [90] with supplement. Abbreviations: MUFAs, monounsaturated fatty acids; PUFAs, polyunsaturated fatty acids; CYP7a1, cholesterol 7α-hydroxylase; ABC, ATP-binding cassette (transporter); ACAT2, acyl-CoA:cholesterol acyltransferase, isoform 2; HMG-CoA R, HMG-CoA reductase; NPC1L1, Niemann-Pick C1-Like 1; SR-BI, scavenger receptor class B member I; MTP, microsomal triglyceride transfer protein; APO, apolipoprotein; LXR, liver X receptor; FXR, farnesoid X receptor; RXR, retinoid X receptor; PPAR, peroxisomal proliferator activated receptor; CCK, cholecystokinin; MUC, mucin gene; CEL, carboxyl ester lipase; PTL, pancreatic triglyceride lipase; ↑ increase, ↓ decrease, (-) no influence. Contradictory result from different research groups.