Skip to main content
Top
Published in: BMC Complementary Medicine and Therapies 1/2017

Open Access 01-12-2017 | Research article

Anti-diarrheal and anti-inflammatory activities of aqueous extract of the aerial part of Rubia cordifolia

Authors: Xue-Peng Gong, Yuan-Yuan Sun, Wei Chen, Xia Guo, Jian-Kun Guan, Dong-Yan Li, Guang Du

Published in: BMC Complementary Medicine and Therapies | Issue 1/2017

Login to get access

Abstract

Background

In Shaanxi province, China, the aqueous extract of Rubia cordifolia’s aerial part (AERCAP) is traditionally used to manage diarrhea. However, there is no scientific evidence to verify the safety and efficacy of its use. The aim of this study was to investigate the anti-diarrheal and anti-inflammatory effects of AERCAP by using a rodent model.

Methods

The anti-diarrheal effects were studied by senna leaf-induced diarrheal and intestinal transit experiments in mice. The anti-inflammatory activity was investigated by trinitrobenzenesulfonic acid (TNBS)-induced colonic inflammation in rats.

Results

The results indicated that AERCAP delayed the onset of semi-solid feces, reduced the evacuation index (EI) in senna leaf-induced diarrheal in mice, and inhibited the propulsive movement in castor oil-induced intestinal transit but not in the normal intestinal transit test. The results were compared with the standard anti-diarrheal drug loperamide. Additionally, oral treatment with AERCAP significantly decreased the macroscopic damage area, improved the microscopic structure, and reduced the malondialdehyde (MDA) content, IL-1β and TNF-α levels in colonic tissue compared with the TNBS control group in rats.

Conclusions

AERCAP exhibited anti-diarrheal and anti-inflammatory activities in a rodent model. The study validated the traditional use of the plant in Chinese herbal medicine as a valuable natural remedy for the treatment of diarrhea.
Literature
1.
go back to reference Suleiman MM, Dzenda T, Sani CA. Antidiarrhoeal activity of the methanol stem-bark extract of Annona senegalensis Pers. (Annonaceae). J Ethnopharmacol. 2008;116:125–30.CrossRefPubMed Suleiman MM, Dzenda T, Sani CA. Antidiarrhoeal activity of the methanol stem-bark extract of Annona senegalensis Pers. (Annonaceae). J Ethnopharmacol. 2008;116:125–30.CrossRefPubMed
2.
go back to reference Agunu A, Yusuf S, Andrew GO, Zezi AU, Abdurahman EM. Evaluation of five medicinal plants used in diarrhoea treatment in Nigeria. J Ethnopharmacol. 2005;101(1–3):27–30.CrossRefPubMed Agunu A, Yusuf S, Andrew GO, Zezi AU, Abdurahman EM. Evaluation of five medicinal plants used in diarrhoea treatment in Nigeria. J Ethnopharmacol. 2005;101(1–3):27–30.CrossRefPubMed
3.
go back to reference Kosek M, Bern C, Guerrant RL. The global burden of diarrhoeal disease, as estimated from studies published between 1992 and 2000. Bull World Health Organ. 2003;81:197–204.PubMedPubMedCentral Kosek M, Bern C, Guerrant RL. The global burden of diarrhoeal disease, as estimated from studies published between 1992 and 2000. Bull World Health Organ. 2003;81:197–204.PubMedPubMedCentral
4.
go back to reference Tripathi YB, Pandey S, Shukla SD. Anti-platelet activating factor property of Rubia cordifolia Linn. Indian J Exp Biol. 1993;31:533–5.PubMed Tripathi YB, Pandey S, Shukla SD. Anti-platelet activating factor property of Rubia cordifolia Linn. Indian J Exp Biol. 1993;31:533–5.PubMed
5.
go back to reference Brijesh S, Daswani P, Tetali P, Antia N, Birdi T. Studies on the antidiarrhoeal activity of Aegle marmelos unripe fruit: validating its traditional usage. BMC Complement Altern Med. 2009;9:47.CrossRefPubMedPubMedCentral Brijesh S, Daswani P, Tetali P, Antia N, Birdi T. Studies on the antidiarrhoeal activity of Aegle marmelos unripe fruit: validating its traditional usage. BMC Complement Altern Med. 2009;9:47.CrossRefPubMedPubMedCentral
6.
go back to reference Jun DY, Han CR, Lee JY, Park W, Choi MS, Woo MH, Kim YH. Anti-adipogenic activity of 2-carbomethoxy-2,3-epoxy-3-prenyl-1,4-naphthoquinone from Rubia cordifolia L. J Med Food. 2011;14:454–61.CrossRefPubMed Jun DY, Han CR, Lee JY, Park W, Choi MS, Woo MH, Kim YH. Anti-adipogenic activity of 2-carbomethoxy-2,3-epoxy-3-prenyl-1,4-naphthoquinone from Rubia cordifolia L. J Med Food. 2011;14:454–61.CrossRefPubMed
7.
go back to reference Jingmei S, Shiyan J, Qiumin Z. Efficacy observation of infantile acute diarrhea treated adjunctively with erxieting. World J Integr Traditional Western Med. 2014;9:1318–20. Jingmei S, Shiyan J, Qiumin Z. Efficacy observation of infantile acute diarrhea treated adjunctively with erxieting. World J Integr Traditional Western Med. 2014;9:1318–20.
8.
go back to reference The editorial board of Chinese Materia Medica. Chinese Materia Medica Mongolia Volume. Shanghai: Shanghai Scientific & Technical Publishers; 2004. The editorial board of Chinese Materia Medica. Chinese Materia Medica Mongolia Volume. Shanghai: Shanghai Scientific & Technical Publishers; 2004.
9.
go back to reference Lu Y, Hu R, Dai Z, Pan Y. Preparative separation of anti-oxidative constituents from Rubia cordifolia by column-switching counter-current chromatography. J Sep Sci. 2010;33:2200–5.CrossRefPubMed Lu Y, Hu R, Dai Z, Pan Y. Preparative separation of anti-oxidative constituents from Rubia cordifolia by column-switching counter-current chromatography. J Sep Sci. 2010;33:2200–5.CrossRefPubMed
10.
go back to reference Ndhlala AR, Finnie JF, Van Staden J. Plant composition, pharmacological properties and mutagenic evaluation of a commercial Zulu herbal mixture: lmbiza ephuzwato. J Ethnopharmacol. 2011;133:663–74.CrossRefPubMed Ndhlala AR, Finnie JF, Van Staden J. Plant composition, pharmacological properties and mutagenic evaluation of a commercial Zulu herbal mixture: lmbiza ephuzwato. J Ethnopharmacol. 2011;133:663–74.CrossRefPubMed
11.
go back to reference Kastrue VS, Deshmukh VK, Chopde CT. Anticonvulsant and behavioral action of triterpene isolated from Rubia cordifolia Linn. Indian J Exp Biol. 2000;38:675–80. Kastrue VS, Deshmukh VK, Chopde CT. Anticonvulsant and behavioral action of triterpene isolated from Rubia cordifolia Linn. Indian J Exp Biol. 2000;38:675–80.
12.
go back to reference Ghosh S, Das Sarma M, Patra A, Hazra B. Anti-inflammatory and anticancer compounds isolated from Ventilago madraspatana Gaertn., Rubia cordifolia Linn. and Lantana camara Linn. J Pharm Pharmacol. 2010;62:1158–66.CrossRefPubMed Ghosh S, Das Sarma M, Patra A, Hazra B. Anti-inflammatory and anticancer compounds isolated from Ventilago madraspatana Gaertn., Rubia cordifolia Linn. and Lantana camara Linn. J Pharm Pharmacol. 2010;62:1158–66.CrossRefPubMed
14.
go back to reference Xinsheng Y, Lijun W, Jizhou W. Phytochemistry. 4th ed. Beijing: The People’s Medical Publishing House; 2004. Xinsheng Y, Lijun W, Jizhou W. Phytochemistry. 4th ed. Beijing: The People’s Medical Publishing House; 2004.
15.
go back to reference Chen Q. Research methods in pharmacology of Chinese material medica. 3rd ed. Beijing: The People’s Medical Publishing House; 2011. Chen Q. Research methods in pharmacology of Chinese material medica. 3rd ed. Beijing: The People’s Medical Publishing House; 2011.
16.
go back to reference Zhang J, Wang S, Li Y, Xu P, Chen F, Tan Y, Duan J. Anti-diarrheal constituents of Alpinia oxyphylla. Fitoterapia. 2013;89:149–56.CrossRefPubMed Zhang J, Wang S, Li Y, Xu P, Chen F, Tan Y, Duan J. Anti-diarrheal constituents of Alpinia oxyphylla. Fitoterapia. 2013;89:149–56.CrossRefPubMed
17.
go back to reference Tadesse WT, Hailu AE, Gurmu AE, Mechesso AF. Experimental assessment of antidiarrheal and antisecretory activity of 80% methanolic leaf extract of Zehneria scabra in mice. BMC Complement Altern Med. 2014;14:460.CrossRefPubMedPubMedCentral Tadesse WT, Hailu AE, Gurmu AE, Mechesso AF. Experimental assessment of antidiarrheal and antisecretory activity of 80% methanolic leaf extract of Zehneria scabra in mice. BMC Complement Altern Med. 2014;14:460.CrossRefPubMedPubMedCentral
18.
go back to reference de Sales IR, Machado FD, Marinho AF, Lúcio AS, Barbosa Filho JM, Batista LM. Cissampelos sympodialis Eichl. (Menispermaceae), a medicinal plant, presents antimotility and antidiarrheal activity in vivo. BMC Complement Altern Med. 2015;15:253.CrossRefPubMedPubMedCentral de Sales IR, Machado FD, Marinho AF, Lúcio AS, Barbosa Filho JM, Batista LM. Cissampelos sympodialis Eichl. (Menispermaceae), a medicinal plant, presents antimotility and antidiarrheal activity in vivo. BMC Complement Altern Med. 2015;15:253.CrossRefPubMedPubMedCentral
19.
go back to reference Awe EO, Kolawole SO, Wakeel KO, Abiodun OO. Antidiarrheal activity of Pyrenacantha staudtii Engl. (Icacinaceae) aqueous leaf extract in rodents. J Ethnopharmacol. 2011;137:148–53.CrossRefPubMed Awe EO, Kolawole SO, Wakeel KO, Abiodun OO. Antidiarrheal activity of Pyrenacantha staudtii Engl. (Icacinaceae) aqueous leaf extract in rodents. J Ethnopharmacol. 2011;137:148–53.CrossRefPubMed
20.
go back to reference Pawar P, Gilda S, Sharma S, Jagtap S, Paradkar A, Mahadik K, Ranjekar P, Harsulkar A. Rectal gel application of Withania somnifera root extract expounds anti-inflammatory and muco-restorative activity in TNBS-induced Inflammatory Bowel Disease. BMC Complement Altern Med. 2011;11:34.CrossRefPubMedPubMedCentral Pawar P, Gilda S, Sharma S, Jagtap S, Paradkar A, Mahadik K, Ranjekar P, Harsulkar A. Rectal gel application of Withania somnifera root extract expounds anti-inflammatory and muco-restorative activity in TNBS-induced Inflammatory Bowel Disease. BMC Complement Altern Med. 2011;11:34.CrossRefPubMedPubMedCentral
21.
go back to reference de Almeida AB, Sánchez-Hidalgo M, Martín AR, Luiz-Ferreira A, Trigo JR, Vilegas W, dos Santos LC, Souza-Brito ARM, de la Lastra CA. Anti-inflammatory intestinal activity of Arctium lappa L. (Asteraceae) in TNBS colitis model. J Ethnopharmacol. 2013;146:300–10.CrossRefPubMed de Almeida AB, Sánchez-Hidalgo M, Martín AR, Luiz-Ferreira A, Trigo JR, Vilegas W, dos Santos LC, Souza-Brito ARM, de la Lastra CA. Anti-inflammatory intestinal activity of Arctium lappa L. (Asteraceae) in TNBS colitis model. J Ethnopharmacol. 2013;146:300–10.CrossRefPubMed
22.
23.
go back to reference Ajayi CO, Funso-Babarimisa F, Elujoba AA. Laxative activities of Cassia sieberiana and Senna obtusifolia. Afr J Tradit Complement Altern Med. 2014;11:44–7.CrossRefPubMedPubMedCentral Ajayi CO, Funso-Babarimisa F, Elujoba AA. Laxative activities of Cassia sieberiana and Senna obtusifolia. Afr J Tradit Complement Altern Med. 2014;11:44–7.CrossRefPubMedPubMedCentral
24.
go back to reference Goppel M, Franz G. Stability control of senna leaves and senna extracts. Planta Med. 2004;70:432–6.CrossRefPubMed Goppel M, Franz G. Stability control of senna leaves and senna extracts. Planta Med. 2004;70:432–6.CrossRefPubMed
25.
go back to reference Izzo AA, Gaginella TS, Mascolo N, Borrelli F, Capasso F. NG-nitro-L-arginine methyl ester reduces senna- and cascara-induced diarrhoea and fluid secretion in the rat. Eur J Pharmacoll. 1996;301:137–42.CrossRef Izzo AA, Gaginella TS, Mascolo N, Borrelli F, Capasso F. NG-nitro-L-arginine methyl ester reduces senna- and cascara-induced diarrhoea and fluid secretion in the rat. Eur J Pharmacoll. 1996;301:137–42.CrossRef
26.
go back to reference Weisbrodt NW, Badial-Aceves F, Dudrick SJ, Burks TF, Castro GA. Tolerance to the effect of morphine on intestinal transit. Proc soc exp boil med. 1977;154(4):587–90.CrossRef Weisbrodt NW, Badial-Aceves F, Dudrick SJ, Burks TF, Castro GA. Tolerance to the effect of morphine on intestinal transit. Proc soc exp boil med. 1977;154(4):587–90.CrossRef
27.
go back to reference Suleiman MM, Dzenda T, Sani CA. Antidiarrhoeal activity of the methanol stem-bark extract of Annona senegalensis Pers. (Annonaceae). J Ethnopharmacol. 2008;116(1):125–30.CrossRefPubMed Suleiman MM, Dzenda T, Sani CA. Antidiarrhoeal activity of the methanol stem-bark extract of Annona senegalensis Pers. (Annonaceae). J Ethnopharmacol. 2008;116(1):125–30.CrossRefPubMed
28.
go back to reference Bhuiyan M, Fant ME, Dasgupta A. Study on mechanism of action of Chinese medicine Chan Su: dose-dependent biphasic production of nitric oxide in trophoblastic BeWo cells. Clin Chim Acta. 2003;330(1–2):179–84.CrossRefPubMed Bhuiyan M, Fant ME, Dasgupta A. Study on mechanism of action of Chinese medicine Chan Su: dose-dependent biphasic production of nitric oxide in trophoblastic BeWo cells. Clin Chim Acta. 2003;330(1–2):179–84.CrossRefPubMed
29.
go back to reference Tang SH, Chen JX, Wang YP, Wang L, Yang HJ. Research ideas and strategies on the dose-effect relationship of traditional Chinese medicine prescriptions and herbs. J Tradit Chin Med. 2012;32(1):110–3.CrossRefPubMed Tang SH, Chen JX, Wang YP, Wang L, Yang HJ. Research ideas and strategies on the dose-effect relationship of traditional Chinese medicine prescriptions and herbs. J Tradit Chin Med. 2012;32(1):110–3.CrossRefPubMed
30.
go back to reference Chittrakarn S, Sawangjaroen K, Prasettho S, Janchawee B, Keawpradub N. Inhibitory effects of kratom leaf extract (Mitragyna speciosa Korth.) on the rat gastrointestinal tract. J Ethnopharmacol. 2008;116:173–8.CrossRefPubMed Chittrakarn S, Sawangjaroen K, Prasettho S, Janchawee B, Keawpradub N. Inhibitory effects of kratom leaf extract (Mitragyna speciosa Korth.) on the rat gastrointestinal tract. J Ethnopharmacol. 2008;116:173–8.CrossRefPubMed
31.
go back to reference Gilani AH, Janbaz KH, Zaman M, Lateef A, Suria A, Ahmed HR. Possible presence of calcium channel blocker(s) in Rubia cordifolia: an indigenous medicinal plant. J Pak Med Assoc. 1994;44(4):82–5.PubMed Gilani AH, Janbaz KH, Zaman M, Lateef A, Suria A, Ahmed HR. Possible presence of calcium channel blocker(s) in Rubia cordifolia: an indigenous medicinal plant. J Pak Med Assoc. 1994;44(4):82–5.PubMed
32.
go back to reference Weisbrodt NW, Sussman SS, Stewart JJ, Burks TF. Effect of morphine sulfate on intestinal transit and myoelectric activity of the small intestine of the rat. J Pharmcol exp ther. 1980;214(2):333–8. Weisbrodt NW, Sussman SS, Stewart JJ, Burks TF. Effect of morphine sulfate on intestinal transit and myoelectric activity of the small intestine of the rat. J Pharmcol exp ther. 1980;214(2):333–8.
33.
go back to reference Capasso F, Mascolo N, Izzo AA, Gaginella TS. Dissociation of castor oil-induced diarrhea and intestinal mucosal injury in rat: effect of NG-nitro-L-arginine methylester. Br J Pharmacol. 1994;113:1127–30.CrossRefPubMedPubMedCentral Capasso F, Mascolo N, Izzo AA, Gaginella TS. Dissociation of castor oil-induced diarrhea and intestinal mucosal injury in rat: effect of NG-nitro-L-arginine methylester. Br J Pharmacol. 1994;113:1127–30.CrossRefPubMedPubMedCentral
34.
go back to reference Baumgart DC, Sandborn WJ. Inflammatory bowel disease: clinical aspects and established and evolving therapies. Lancet. 2007;369:1641–57.CrossRefPubMed Baumgart DC, Sandborn WJ. Inflammatory bowel disease: clinical aspects and established and evolving therapies. Lancet. 2007;369:1641–57.CrossRefPubMed
35.
go back to reference Baumgart DC, Carding SR. Inflammatory bowel disease: cause and immunobiology. Lancet. 2007;369:1627–40.CrossRefPubMed Baumgart DC, Carding SR. Inflammatory bowel disease: cause and immunobiology. Lancet. 2007;369:1627–40.CrossRefPubMed
36.
go back to reference Kruidenier L, Kuiper I, Lamers CB, Verspaget HW. Intestinal oxidative damage in inflammatory bowel disease: semi-quantification, localization, and association with mucosal antioxidants. J Pathol. 2003;201:28–36.CrossRefPubMed Kruidenier L, Kuiper I, Lamers CB, Verspaget HW. Intestinal oxidative damage in inflammatory bowel disease: semi-quantification, localization, and association with mucosal antioxidants. J Pathol. 2003;201:28–36.CrossRefPubMed
37.
go back to reference Masoodi I, Tijjani BM, Wani H, Hassan NS, Khan AB, Hussain S. Biomarkers in the management of ulcerative colitis: a brief review. Ger Med Sci. 2011;9:Doc03.PubMedPubMedCentral Masoodi I, Tijjani BM, Wani H, Hassan NS, Khan AB, Hussain S. Biomarkers in the management of ulcerative colitis: a brief review. Ger Med Sci. 2011;9:Doc03.PubMedPubMedCentral
38.
go back to reference Wang J, Fu YX. Tumor necrosis factor family members and inflammatory bowel disease. Immunol Rev. 2005;204:144–55.CrossRefPubMed Wang J, Fu YX. Tumor necrosis factor family members and inflammatory bowel disease. Immunol Rev. 2005;204:144–55.CrossRefPubMed
39.
go back to reference Te Velde AA, Verstege MI, Hommes DW. Critical appraisal of the current practice in murine TNBS-induced colitis. Inflamm Bowel Dis. 2006;12:995–9.CrossRef Te Velde AA, Verstege MI, Hommes DW. Critical appraisal of the current practice in murine TNBS-induced colitis. Inflamm Bowel Dis. 2006;12:995–9.CrossRef
40.
go back to reference Mazzolin L, Kiguti LR, da Maia EO, Fernandes LT, da Rocha LR, Vilegas W, Pupo AS, Di Stasi LC, Hiruma-Lima CA. Antidiarrheal and intestinal antiinflammatory activities of a methanolic extract of Qualea parviflora Mart. in experimental models. J Ethnopharmacol. 2013;150:1016–23.CrossRefPubMed Mazzolin L, Kiguti LR, da Maia EO, Fernandes LT, da Rocha LR, Vilegas W, Pupo AS, Di Stasi LC, Hiruma-Lima CA. Antidiarrheal and intestinal antiinflammatory activities of a methanolic extract of Qualea parviflora Mart. in experimental models. J Ethnopharmacol. 2013;150:1016–23.CrossRefPubMed
41.
go back to reference Da Silva MS, Sánchez-Fidalgo S, Talero E, Cárdeno A, da Silva MA, Villegas W, Souza Brito AR, de La Lastra CA. Anti-inflammatory intestinal activity of Abarema cochliacarpos (Gomes) Barneby & Grimes in TNBS colitis model. J Ethnopharmacol. 2010;128:467–75.CrossRefPubMed Da Silva MS, Sánchez-Fidalgo S, Talero E, Cárdeno A, da Silva MA, Villegas W, Souza Brito AR, de La Lastra CA. Anti-inflammatory intestinal activity of Abarema cochliacarpos (Gomes) Barneby & Grimes in TNBS colitis model. J Ethnopharmacol. 2010;128:467–75.CrossRefPubMed
42.
go back to reference Ukil A, Maity S, Karmakar S, Datta N, Vedasiromoni JR, Das PK. Curcumin, the major component of food flavour turmeric, reduces mucosal injury in trinitrobenzene sulphonic acid-induced colitis. Br J Pharmacol. 2003;139:209–18.CrossRefPubMedPubMedCentral Ukil A, Maity S, Karmakar S, Datta N, Vedasiromoni JR, Das PK. Curcumin, the major component of food flavour turmeric, reduces mucosal injury in trinitrobenzene sulphonic acid-induced colitis. Br J Pharmacol. 2003;139:209–18.CrossRefPubMedPubMedCentral
43.
go back to reference Jagtap AG, Shirke SS, Phadke AS. Effect of polyherbal formulation on experimental models of inflammatory bowel diseases. J Ethnopharmacol. 2004;90:195–204.CrossRefPubMed Jagtap AG, Shirke SS, Phadke AS. Effect of polyherbal formulation on experimental models of inflammatory bowel diseases. J Ethnopharmacol. 2004;90:195–204.CrossRefPubMed
44.
go back to reference Halliwell B, Gutteridge JM, Cross CE. Free radicals, antioxidants, and human disease: where are we now? J Lab Clin Med. 1992;119:598–620.PubMed Halliwell B, Gutteridge JM, Cross CE. Free radicals, antioxidants, and human disease: where are we now? J Lab Clin Med. 1992;119:598–620.PubMed
45.
go back to reference Sebai H, Jabri MA, Souli A, Rtibi K, Selmi S, Tebourbi O, El-Benna J, Sakly M. Antidiarrheal and antioxidant activities of chamomile (Matricaria recutita L.) decoction extract in rats. J Ethnopharmacol. 2014;152:327–32.CrossRefPubMed Sebai H, Jabri MA, Souli A, Rtibi K, Selmi S, Tebourbi O, El-Benna J, Sakly M. Antidiarrheal and antioxidant activities of chamomile (Matricaria recutita L.) decoction extract in rats. J Ethnopharmacol. 2014;152:327–32.CrossRefPubMed
46.
go back to reference Kim SJ, Kim MC, Um JY, Hong SH. The beneficial effect of vanillic acid on ulcerative colitis. Molecules. 2010;15(10):7208–17.CrossRefPubMed Kim SJ, Kim MC, Um JY, Hong SH. The beneficial effect of vanillic acid on ulcerative colitis. Molecules. 2010;15(10):7208–17.CrossRefPubMed
47.
go back to reference Perez GS, Zavala MD, Soto PC, Sanchez SO, Zavala SM. Evaluation of the anti-diarrheal activity of Salvia connivens. Pharm boil. 2014;52(11):1467–70.CrossRef Perez GS, Zavala MD, Soto PC, Sanchez SO, Zavala SM. Evaluation of the anti-diarrheal activity of Salvia connivens. Pharm boil. 2014;52(11):1467–70.CrossRef
Metadata
Title
Anti-diarrheal and anti-inflammatory activities of aqueous extract of the aerial part of Rubia cordifolia
Authors
Xue-Peng Gong
Yuan-Yuan Sun
Wei Chen
Xia Guo
Jian-Kun Guan
Dong-Yan Li
Guang Du
Publication date
01-12-2017
Publisher
BioMed Central
Published in
BMC Complementary Medicine and Therapies / Issue 1/2017
Electronic ISSN: 2662-7671
DOI
https://doi.org/10.1186/s12906-016-1527-9

Other articles of this Issue 1/2017

BMC Complementary Medicine and Therapies 1/2017 Go to the issue